diff --git a/.python-version b/.python-version
index d70c8f8d89f2..c8cfe3959183 100644
--- a/.python-version
+++ b/.python-version
@@ -1 +1 @@
-3.6
+3.10
diff --git a/agent/conf/agent.properties b/agent/conf/agent.properties
index 3b6a7b7de292..3fc7d4757cee 100644
--- a/agent/conf/agent.properties
+++ b/agent/conf/agent.properties
@@ -433,3 +433,9 @@ iscsi.session.cleanup.enabled=false
 
 # Implicit host tags managed by agent.properties
 # host.tags=
+
+# Timeout(in seconds) for SSL handshake when agent connects to server
+#ssl.handshake.timeout=
+
+# Wait(in seconds) during agent reconnections
+#backoff.seconds=
diff --git a/agent/src/main/java/com/cloud/agent/Agent.java b/agent/src/main/java/com/cloud/agent/Agent.java
index 15f010808aca..7de5c48c6d13 100644
--- a/agent/src/main/java/com/cloud/agent/Agent.java
+++ b/agent/src/main/java/com/cloud/agent/Agent.java
@@ -26,24 +26,25 @@
 import java.net.UnknownHostException;
 import java.nio.channels.ClosedChannelException;
 import java.nio.charset.Charset;
-import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
-import java.util.Timer;
+import java.util.concurrent.CopyOnWriteArrayList;
 import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
 import java.util.concurrent.LinkedBlockingQueue;
+import java.util.concurrent.ScheduledExecutorService;
+import java.util.concurrent.ScheduledFuture;
 import java.util.concurrent.SynchronousQueue;
 import java.util.concurrent.ThreadPoolExecutor;
 import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.concurrent.atomic.AtomicInteger;
+import java.util.concurrent.atomic.AtomicLong;
+import java.util.concurrent.atomic.AtomicReference;
 
 import javax.naming.ConfigurationException;
 
-import com.cloud.resource.AgentStatusUpdater;
-import com.cloud.resource.ResourceStatusUpdater;
-import com.cloud.agent.api.PingAnswer;
-import com.cloud.utils.NumbersUtil;
 import org.apache.cloudstack.agent.lb.SetupMSListAnswer;
 import org.apache.cloudstack.agent.lb.SetupMSListCommand;
 import org.apache.cloudstack.ca.PostCertificateRenewalCommand;
@@ -55,10 +56,10 @@
 import org.apache.cloudstack.utils.security.KeyStoreUtils;
 import org.apache.commons.collections.CollectionUtils;
 import org.apache.commons.io.FileUtils;
-import org.apache.commons.lang.ObjectUtils;
 import org.apache.commons.lang3.StringUtils;
-import org.apache.logging.log4j.Logger;
 import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+import org.apache.logging.log4j.ThreadContext;
 
 import com.cloud.agent.api.AgentControlAnswer;
 import com.cloud.agent.api.AgentControlCommand;
@@ -67,6 +68,7 @@
 import com.cloud.agent.api.CronCommand;
 import com.cloud.agent.api.MaintainAnswer;
 import com.cloud.agent.api.MaintainCommand;
+import com.cloud.agent.api.PingAnswer;
 import com.cloud.agent.api.PingCommand;
 import com.cloud.agent.api.ReadyCommand;
 import com.cloud.agent.api.ShutdownCommand;
@@ -76,9 +78,11 @@
 import com.cloud.agent.transport.Response;
 import com.cloud.exception.AgentControlChannelException;
 import com.cloud.host.Host;
+import com.cloud.resource.AgentStatusUpdater;
+import com.cloud.resource.ResourceStatusUpdater;
 import com.cloud.resource.ServerResource;
+import com.cloud.utils.NumbersUtil;
 import com.cloud.utils.PropertiesUtil;
-import com.cloud.utils.backoff.BackoffAlgorithm;
 import com.cloud.utils.concurrency.NamedThreadFactory;
 import com.cloud.utils.exception.CloudRuntimeException;
 import com.cloud.utils.exception.NioConnectionException;
@@ -90,7 +94,6 @@
 import com.cloud.utils.nio.Task;
 import com.cloud.utils.script.OutputInterpreter;
 import com.cloud.utils.script.Script;
-import org.apache.logging.log4j.ThreadContext;
 
 /**
  * @config
@@ -114,7 +117,7 @@ public enum ExitStatus {
         Configuration(66), // Exiting due to configuration problems.
         Error(67); // Exiting because of error.
 
-        int value;
+        final int value;
 
         ExitStatus(final int value) {
             this.value = value;
@@ -125,128 +128,134 @@ public int value() {
         }
     }
 
-    List<IAgentControlListener> _controlListeners = new ArrayList<IAgentControlListener>();
+    CopyOnWriteArrayList<IAgentControlListener> controlListeners = new CopyOnWriteArrayList<>();
 
-    IAgentShell _shell;
-    NioConnection _connection;
-    ServerResource _resource;
-    Link _link;
-    Long _id;
+    IAgentShell shell;
+    NioConnection connection;
+    ServerResource serverResource;
+    Link link;
+    Long id;
 
-    Timer _timer = new Timer("Agent Timer");
-    Timer certTimer;
-    Timer hostLBTimer;
+    ScheduledExecutorService selfTaskExecutor;
+    ScheduledExecutorService certExecutor;
+    ScheduledExecutorService hostLbCheckExecutor;
 
-    List<WatchTask> _watchList = new ArrayList<WatchTask>();
-    long _sequence = 0;
-    long _lastPingResponseTime = 0;
-    long _pingInterval = 0;
-    AtomicInteger _inProgress = new AtomicInteger();
+    CopyOnWriteArrayList<ScheduledFuture<?>> watchList = new CopyOnWriteArrayList<>();
+    AtomicLong sequence = new AtomicLong(0);
+    AtomicLong lastPingResponseTime = new AtomicLong(0L);
+    long pingInterval = 0;
+    AtomicInteger commandsInProgress = new AtomicInteger(0);
 
-    StartupTask _startup = null;
-    long _startupWaitDefault = 180000;
-    long _startupWait = _startupWaitDefault;
-    boolean _reconnectAllowed = true;
-    //For time sentitive task, e.g. PingTask
-    ThreadPoolExecutor _ugentTaskPool;
-    ExecutorService _executor;
+    private final AtomicReference<StartupTask> startupTask = new AtomicReference<>();
+    private static final long DEFAULT_STARTUP_WAIT = 180;
+    long startupWait = DEFAULT_STARTUP_WAIT;
+    boolean reconnectAllowed = true;
 
-    Thread _shutdownThread = new ShutdownThread(this);
+    //For time sensitive task, e.g. PingTask
+    ThreadPoolExecutor outRequestHandler;
+    ExecutorService requestHandler;
 
-    private String _keystoreSetupPath;
-    private String _keystoreCertImportPath;
+    Thread shutdownThread = new ShutdownThread(this);
 
-    // for simulator use only
-    public Agent(final IAgentShell shell) {
-        _shell = shell;
-        _link = null;
+    private String keystoreSetupSetupPath;
+    private String keystoreCertImportScriptPath;
 
-        _connection = new NioClient("Agent", _shell.getNextHost(), _shell.getPort(), _shell.getWorkers(), this);
+    private String hostname;
 
-        Runtime.getRuntime().addShutdownHook(_shutdownThread);
+    private String getLinkLog(final Link link) {
+        if (link == null) {
+            return "";
+        }
+        StringBuilder str = new StringBuilder();
+        if (logger.isTraceEnabled()) {
+            str.append(System.identityHashCode(link)).append("-");
+        }
+        str.append(link.getSocketAddress());
+        return str.toString();
+    }
 
-        _ugentTaskPool =
-                new ThreadPoolExecutor(shell.getPingRetries(), 2 * shell.getPingRetries(), 10, TimeUnit.MINUTES, new SynchronousQueue<Runnable>(), new NamedThreadFactory(
-                        "UgentTask"));
+    private String getAgentName() {
+        return (serverResource != null && serverResource.isAppendAgentNameToLogs() &&
+                StringUtils.isNotBlank(serverResource.getName())) ?
+                serverResource.getName() :
+                "Agent";
+    }
 
-        _executor =
-                new ThreadPoolExecutor(_shell.getWorkers(), 5 * _shell.getWorkers(), 1, TimeUnit.DAYS, new LinkedBlockingQueue<Runnable>(), new NamedThreadFactory(
-                        "agentRequest-Handler"));
+    private void setupShutdownHookAndInitExecutors() {
+        if (logger.isTraceEnabled()) {
+            logger.trace("Adding shutdown hook");
+        }
+        Runtime.getRuntime().addShutdownHook(shutdownThread);
+        selfTaskExecutor = Executors.newScheduledThreadPool(1, new NamedThreadFactory("Agent-SelfTask"));
+        outRequestHandler = new ThreadPoolExecutor(shell.getPingRetries(), 2 * shell.getPingRetries(), 10, TimeUnit.MINUTES,
+                new SynchronousQueue<>(), new NamedThreadFactory("AgentOutRequest-Handler"));
+        requestHandler = new ThreadPoolExecutor(shell.getWorkers(), 5 * shell.getWorkers(), 1, TimeUnit.DAYS,
+                new LinkedBlockingQueue<>(), new NamedThreadFactory("AgentRequest-Handler"));
     }
 
-    public Agent(final IAgentShell shell, final int localAgentId, final ServerResource resource) throws ConfigurationException {
-        _shell = shell;
-        _resource = resource;
-        _link = null;
+    // for simulator use only
+    public Agent(final IAgentShell shell) {
+        this.shell = shell;
+        link = null;
+        connection = new NioClient(getAgentName(), this.shell.getNextHost(), this.shell.getPort(),
+                this.shell.getWorkers(), this.shell.getSslHandshakeTimeout(), this);
+        setupShutdownHookAndInitExecutors();
+    }
 
+    public Agent(final IAgentShell shell, final int localAgentId, final ServerResource resource) throws ConfigurationException {
+        this.shell = shell;
+        serverResource = resource;
+        link = null;
         resource.setAgentControl(this);
-
-        final String value = _shell.getPersistentProperty(getResourceName(), "id");
-        _id = value != null ? Long.parseLong(value) : null;
-        logger.info("id is {}", ObjectUtils.defaultIfNull(_id, ""));
-
+        final String value = this.shell.getPersistentProperty(getResourceName(), "id");
+        id = value != null ? Long.parseLong(value) : null;
+        logger.info("id is {}", (id != null ? id : ""));
         final Map<String, Object> params = new HashMap<>();
-
         // merge with properties from command line to let resource access command line parameters
-        for (final Map.Entry<String, Object> cmdLineProp : _shell.getCmdLineProperties().entrySet()) {
+        for (final Map.Entry<String, Object> cmdLineProp : this.shell.getCmdLineProperties().entrySet()) {
             params.put(cmdLineProp.getKey(), cmdLineProp.getValue());
         }
-
-        if (!_resource.configure(getResourceName(), params)) {
-            throw new ConfigurationException("Unable to configure " + _resource.getName());
-        }
-
-        final String host = _shell.getNextHost();
-        _connection = new NioClient("Agent", host, _shell.getPort(), _shell.getWorkers(), this);
-
-        // ((NioClient)_connection).setBindAddress(_shell.getPrivateIp());
-
-        logger.debug("Adding shutdown hook");
-        Runtime.getRuntime().addShutdownHook(_shutdownThread);
-
-        _ugentTaskPool =
-                new ThreadPoolExecutor(shell.getPingRetries(), 2 * shell.getPingRetries(), 10, TimeUnit.MINUTES, new SynchronousQueue<Runnable>(), new NamedThreadFactory(
-                        "UgentTask"));
-
-        _executor =
-                new ThreadPoolExecutor(_shell.getWorkers(), 5 * _shell.getWorkers(), 1, TimeUnit.DAYS, new LinkedBlockingQueue<Runnable>(), new NamedThreadFactory(
-                        "agentRequest-Handler"));
-
-        logger.info("Agent [id = {} : type = {} : zone = {} : pod = {} : workers = {} : host = {} : port = {}", ObjectUtils.defaultIfNull(_id, "new"), getResourceName(),
-                 _shell.getZone(), _shell.getPod(), _shell.getWorkers(), host, _shell.getPort());
+        if (!serverResource.configure(getResourceName(), params)) {
+            throw new ConfigurationException("Unable to configure " + serverResource.getName());
+        }
+        ThreadContext.put("agentname", getAgentName());
+        final String host = this.shell.getNextHost();
+        connection = new NioClient(getAgentName(), host, this.shell.getPort(), this.shell.getWorkers(),
+                this.shell.getSslHandshakeTimeout(), this);
+        setupShutdownHookAndInitExecutors();
+        logger.info("Agent [id = {}, type = {}, zone = {}, pod = {}, workers = {}, host = {}, " +
+                        "port = {}, local id = {}]",
+                (id != null ? String.valueOf(id) : "new"), getResourceName(), this.shell.getZone(),
+                this.shell.getPod(), this.shell.getWorkers(), host, this.shell.getPort(), localAgentId);
     }
 
     public String getVersion() {
-        return _shell.getVersion();
+        return shell.getVersion();
     }
 
     public String getResourceGuid() {
-        final String guid = _shell.getGuid();
+        final String guid = shell.getGuid();
         return guid + "-" + getResourceName();
     }
 
     public String getZone() {
-        return _shell.getZone();
+        return shell.getZone();
     }
 
     public String getPod() {
-        return _shell.getPod();
+        return shell.getPod();
     }
 
     protected void setLink(final Link link) {
-        _link = link;
+        this.link = link;
     }
 
     public ServerResource getResource() {
-        return _resource;
-    }
-
-    public BackoffAlgorithm getBackoffAlgorithm() {
-        return _shell.getBackoffAlgorithm();
+        return serverResource;
     }
 
     public String getResourceName() {
-        return _resource.getClass().getSimpleName();
+        return serverResource.getClass().getSimpleName();
     }
 
     /**
@@ -255,71 +264,65 @@ public String getResourceName() {
      * agent instances and its inner objects.
      */
     private void scavengeOldAgentObjects() {
-        _executor.submit(new Runnable() {
-            @Override
-            public void run() {
-                try {
-                    Thread.sleep(2000L);
-                } catch (final InterruptedException ignored) {
-                } finally {
-                    System.gc();
-                }
+        requestHandler.submit(() -> {
+            try {
+                Thread.sleep(2000L);
+            } catch (final InterruptedException ignored) {
+            } finally {
+                System.gc();
             }
         });
     }
 
     public void start() {
-        if (!_resource.start()) {
-            logger.error("Unable to start the resource: {}", _resource.getName());
-            throw new CloudRuntimeException("Unable to start the resource: " + _resource.getName());
+        if (!serverResource.start()) {
+            String msg = String.format("Unable to start the resource: %s", serverResource.getName());
+            logger.error(msg);
+            throw new CloudRuntimeException(msg);
         }
 
-        _keystoreSetupPath = Script.findScript("scripts/util/", KeyStoreUtils.KS_SETUP_SCRIPT);
-        if (_keystoreSetupPath == null) {
+        keystoreSetupSetupPath = Script.findScript("scripts/util/", KeyStoreUtils.KS_SETUP_SCRIPT);
+        if (keystoreSetupSetupPath == null) {
             throw new CloudRuntimeException(String.format("Unable to find the '%s' script", KeyStoreUtils.KS_SETUP_SCRIPT));
         }
 
-        _keystoreCertImportPath = Script.findScript("scripts/util/", KeyStoreUtils.KS_IMPORT_SCRIPT);
-        if (_keystoreCertImportPath == null) {
+        keystoreCertImportScriptPath = Script.findScript("scripts/util/", KeyStoreUtils.KS_IMPORT_SCRIPT);
+        if (keystoreCertImportScriptPath == null) {
             throw new CloudRuntimeException(String.format("Unable to find the '%s' script", KeyStoreUtils.KS_IMPORT_SCRIPT));
         }
 
         try {
-            _connection.start();
+            connection.start();
         } catch (final NioConnectionException e) {
             logger.warn("Attempt to connect to server generated NIO Connection Exception {}, trying again", e.getLocalizedMessage());
         }
-        while (!_connection.isStartup()) {
-            final String host = _shell.getNextHost();
-            _shell.getBackoffAlgorithm().waitBeforeRetry();
-            _connection = new NioClient("Agent", host, _shell.getPort(), _shell.getWorkers(), this);
-            logger.info("Connecting to host:{}", host);
+        while (!connection.isStartup()) {
+            final String host = shell.getNextHost();
+            shell.getBackoffAlgorithm().waitBeforeRetry();
+            connection = new NioClient(getAgentName(), host, shell.getPort(), shell.getWorkers(),
+                    shell.getSslHandshakeTimeout(), this);
+            logger.info("Connecting to host: {}", host);
             try {
-                _connection.start();
+                connection.start();
             } catch (final NioConnectionException e) {
-                _connection.stop();
-                try {
-                    _connection.cleanUp();
-                } catch (final IOException ex) {
-                    logger.warn("Fail to clean up old connection. {}", ex);
-                }
+                stopAndCleanupConnection(false);
                 logger.info("Attempted to connect to the server, but received an unexpected exception, trying again...", e);
             }
         }
-        _shell.updateConnectedHost();
+        shell.updateConnectedHost();
         scavengeOldAgentObjects();
 
     }
 
     public void stop(final String reason, final String detail) {
-        logger.info("Stopping the agent: Reason = {} {}", reason, ": Detail = "  + ObjectUtils.defaultIfNull(detail, ""));
-        _reconnectAllowed = false;
-        if (_connection != null) {
+        logger.info("Stopping the agent: Reason = {}{}", reason, (detail != null ? ": Detail = " + detail : ""));
+        reconnectAllowed = false;
+        if (connection != null) {
             final ShutdownCommand cmd = new ShutdownCommand(reason, detail);
             try {
-                if (_link != null) {
-                    final Request req = new Request(_id != null ? _id : -1, -1, cmd, false);
-                    _link.send(req.toBytes());
+                if (link != null) {
+                    final Request req = new Request(id != null ? id : -1, -1, cmd, false);
+                    link.send(req.toBytes());
                 }
             } catch (final ClosedChannelException e) {
                 logger.warn("Unable to send: {}", cmd.toString());
@@ -332,108 +335,127 @@ public void stop(final String reason, final String detail) {
             } catch (final InterruptedException e) {
                 logger.debug("Who the heck interrupted me here?");
             }
-            _connection.stop();
-            _connection = null;
-            _link = null;
+            connection.stop();
+            connection = null;
+            link = null;
         }
 
-        if (_resource != null) {
-            _resource.stop();
-            _resource = null;
+        if (serverResource != null) {
+            serverResource.stop();
+            serverResource = null;
         }
 
-        if (_startup != null) {
-            _startup = null;
+        if (startupTask.get() != null) {
+            startupTask.set(null);
         }
 
-        if (_ugentTaskPool != null) {
-            _ugentTaskPool.shutdownNow();
-            _ugentTaskPool = null;
+        if (outRequestHandler != null) {
+            outRequestHandler.shutdownNow();
+            outRequestHandler = null;
         }
 
-        if (_executor != null) {
-            _executor.shutdown();
-            _executor = null;
+        if (requestHandler != null) {
+            requestHandler.shutdown();
+            requestHandler = null;
         }
 
-        if (_timer != null) {
-            _timer.cancel();
-            _timer = null;
+        if (selfTaskExecutor != null) {
+            selfTaskExecutor.shutdown();
+            selfTaskExecutor = null;
         }
 
-        if (hostLBTimer != null) {
-            hostLBTimer.cancel();
-            hostLBTimer = null;
+        if (hostLbCheckExecutor != null) {
+            hostLbCheckExecutor.shutdown();
+            hostLbCheckExecutor = null;
         }
 
-        if (certTimer != null) {
-            certTimer.cancel();
-            certTimer = null;
+        if (certExecutor != null) {
+            certExecutor.shutdown();
+            certExecutor = null;
         }
     }
 
     public Long getId() {
-        return _id;
+        return id;
     }
 
     public void setId(final Long id) {
         logger.debug("Set agent id {}", id);
-        _id = id;
-        _shell.setPersistentProperty(getResourceName(), "id", Long.toString(id));
+        this.id = id;
+        shell.setPersistentProperty(getResourceName(), "id", Long.toString(id));
     }
 
-    private synchronized void scheduleServicesRestartTask() {
-        if (certTimer != null) {
-            certTimer.cancel();
-            certTimer.purge();
+    private void scheduleCertificateRenewalTask() {
+        String name = "CertificateRenewalTask";
+        if (certExecutor != null && !certExecutor.isShutdown()) {
+            certExecutor.shutdown();
+            try {
+                if (!certExecutor.awaitTermination(1, TimeUnit.SECONDS)) {
+                    certExecutor.shutdownNow();
+                }
+            } catch (InterruptedException e) {
+                logger.debug("Forcing {} shutdown as it did not shutdown in the desired time due to: {}",
+                                name, e.getMessage());
+                certExecutor.shutdownNow();
+            }
         }
-        certTimer = new Timer("Certificate Renewal Timer");
-        certTimer.schedule(new PostCertificateRenewalTask(this), 5000L);
+        certExecutor = Executors.newSingleThreadScheduledExecutor((new NamedThreadFactory(name)));
+        certExecutor.schedule(new PostCertificateRenewalTask(this), 5, TimeUnit.SECONDS);
     }
 
     private synchronized void scheduleHostLBCheckerTask(final long checkInterval) {
-        if (hostLBTimer != null) {
-            hostLBTimer.cancel();
+        String name = "HostLBCheckerTask";
+        if (hostLbCheckExecutor != null && !hostLbCheckExecutor.isShutdown()) {
+            hostLbCheckExecutor.shutdown();
+            try {
+                if (!hostLbCheckExecutor.awaitTermination(1, TimeUnit.SECONDS)) {
+                    hostLbCheckExecutor.shutdownNow();
+                }
+            } catch (InterruptedException e) {
+                logger.debug("Forcing {} shutdown as it did not shutdown in the desired time due to: {}",
+                        name, e.getMessage());
+                hostLbCheckExecutor.shutdownNow();
+            }
         }
         if (checkInterval > 0L) {
-            logger.info("Scheduling preferred host timer task with host.lb.interval={}ms", checkInterval);
-            hostLBTimer = new Timer("Host LB Timer");
-            hostLBTimer.scheduleAtFixedRate(new PreferredHostCheckerTask(), checkInterval, checkInterval);
+            logger.info("Scheduling preferred host task with host.lb.interval={}ms", checkInterval);
+            hostLbCheckExecutor = Executors.newSingleThreadScheduledExecutor((new NamedThreadFactory(name)));
+            hostLbCheckExecutor.scheduleAtFixedRate(new PreferredHostCheckerTask(), checkInterval, checkInterval,
+                    TimeUnit.MILLISECONDS);
         }
     }
 
     public void scheduleWatch(final Link link, final Request request, final long delay, final long period) {
-        synchronized (_watchList) {
-            logger.debug("Adding task with request: {} to watch list", request.toString());
 
-            final WatchTask task = new WatchTask(link, request, this);
-            _timer.schedule(task, 0, period);
-            _watchList.add(task);
+        if (logger.isDebugEnabled()) {
+            logger.debug("Adding a watch list");
         }
+        final WatchTask task = new WatchTask(link, request, this);
+        final ScheduledFuture<?> future = selfTaskExecutor.scheduleAtFixedRate(task, delay, period, TimeUnit.MILLISECONDS);
+        watchList.add(future);
     }
 
     public void triggerUpdate() {
-        PingCommand command = _resource.getCurrentStatus(getId());
+        PingCommand command = serverResource.getCurrentStatus(getId());
         command.setOutOfBand(true);
         logger.debug("Sending out of band ping");
-
-        final Request request = new Request(_id, -1, command, false);
+        final Request request = new Request(id, -1, command, false);
         request.setSequence(getNextSequence());
         try {
-            _link.send(request.toBytes());
+            link.send(request.toBytes());
         } catch (final ClosedChannelException e) {
             logger.warn("Unable to send ping update: {}", request.toString());
         }
     }
 
     protected void cancelTasks() {
-        synchronized (_watchList) {
-            for (final WatchTask task : _watchList) {
-                task.cancel();
-            }
-            logger.debug("Clearing {} tasks of watch list", _watchList.size());
-            _watchList.clear();
+        for (final ScheduledFuture<?> task : watchList) {
+            task.cancel(true);
+        }
+        if (logger.isDebugEnabled()) {
+            logger.debug("Clearing watch list: " + watchList.size());
         }
+        watchList.clear();
     }
 
     /**
@@ -444,27 +466,47 @@ protected void cancelTasks() {
      * when host is added back
      */
     protected void cleanupAgentZoneProperties() {
-        _shell.setPersistentProperty(null, "zone", "");
-        _shell.setPersistentProperty(null, "cluster", "");
-        _shell.setPersistentProperty(null, "pod", "");
+        shell.setPersistentProperty(null, "zone", "");
+        shell.setPersistentProperty(null, "cluster", "");
+        shell.setPersistentProperty(null, "pod", "");
+    }
+
+    public void lockStartupTask(final Link link) {
+        logger.debug("Creating startup task for link: {}", getLinkLog(link));
+        StartupTask currentTask = startupTask.get();
+        if (currentTask != null) {
+            logger.warn("A Startup task is already locked or in progress, cannot create for link {}",
+                    getLinkLog(link));
+            return;
+        }
+        currentTask = new StartupTask(link);
+        if (startupTask.compareAndSet(null, currentTask)) {
+            selfTaskExecutor.schedule(currentTask, startupWait, TimeUnit.SECONDS);
+            return;
+        }
+        logger.warn("Failed to lock a StartupTask for link: {}", getLinkLog(link));
     }
 
-    public synchronized void lockStartupTask(final Link link) {
-        _startup = new StartupTask(link);
-        _timer.schedule(_startup, _startupWait);
+    protected boolean cancelStartupTask() {
+        StartupTask task = startupTask.getAndSet(null);
+        if (task != null) {
+            task.cancel();
+            return true;
+        }
+        return false;
     }
 
     public void sendStartup(final Link link) {
-        final StartupCommand[] startup = _resource.initialize();
+        final StartupCommand[] startup = serverResource.initialize();
         if (startup != null) {
-            final String msHostList = _shell.getPersistentProperty(null, "host");
+            final String msHostList = shell.getPersistentProperty(null, "host");
             final Command[] commands = new Command[startup.length];
             for (int i = 0; i < startup.length; i++) {
                 setupStartupCommand(startup[i]);
                 startup[i].setMSHostList(msHostList);
                 commands[i] = startup[i];
             }
-            final Request request = new Request(_id != null ? _id : -1, -1, commands, false, false);
+            final Request request = new Request(id != null ? id : -1, -1, commands, false, false);
             request.setSequence(getNextSequence());
 
             logger.debug("Sending Startup: {}", request.toString());
@@ -472,31 +514,39 @@ public void sendStartup(final Link link) {
             try {
                 link.send(request.toBytes());
             } catch (final ClosedChannelException e) {
-                logger.warn("Unable to send request: {}", request.toString());
+                logger.warn("Unable to send request to {} due to '{}', request: {}",
+                        getLinkLog(link), e.getMessage(), request);
             }
 
-            if (_resource instanceof ResourceStatusUpdater) {
-                ((ResourceStatusUpdater) _resource).registerStatusUpdater(this);
+            if (serverResource instanceof ResourceStatusUpdater) {
+                ((ResourceStatusUpdater) serverResource).registerStatusUpdater(this);
             }
         }
     }
 
-    protected void setupStartupCommand(final StartupCommand startup) {
-        InetAddress addr;
+    protected String retrieveHostname() {
+        if (logger.isTraceEnabled()) {
+            logger.trace(" Retrieving hostname " + serverResource.getClass().getSimpleName());
+        }
+        final String result = Script.runSimpleBashScript(Script.getExecutableAbsolutePath("hostname"), 500);
+        if (StringUtils.isNotBlank(result)) {
+            return result;
+        }
         try {
-            addr = InetAddress.getLocalHost();
+            InetAddress address = InetAddress.getLocalHost();
+            return address.toString();
         } catch (final UnknownHostException e) {
             logger.warn("unknown host? ", e);
             throw new CloudRuntimeException("Cannot get local IP address");
         }
+    }
 
-        final Script command = new Script("hostname", 500, logger);
-        final OutputInterpreter.OneLineParser parser = new OutputInterpreter.OneLineParser();
-        final String result = command.execute(parser);
-        final String hostname = result == null ? parser.getLine() : addr.toString();
-
+    protected void setupStartupCommand(final StartupCommand startup) {
         startup.setId(getId());
-        if (startup.getName() == null) {
+        if (StringUtils.isBlank(startup.getName())) {
+            if (StringUtils.isBlank(hostname)) {
+                hostname = retrieveHostname();
+            }
             startup.setName(hostname);
         }
         startup.setDataCenter(getZone());
@@ -518,78 +568,75 @@ public Task create(final Task.Type type, final Link link, final byte[] data) {
         return new ServerHandler(type, link, data);
     }
 
-    protected void reconnect(final Link link) {
-        if (!_reconnectAllowed) {
+    protected void closeAndTerminateLink(final Link link) {
+        if (link == null) {
             return;
         }
-        synchronized (this) {
-            if (_startup != null) {
-                _startup.cancel();
-                _startup = null;
-            }
-        }
+        link.close();
+        link.terminated();
+    }
 
-        if (link != null) {
-            link.close();
-            link.terminated();
+    protected void stopAndCleanupConnection(boolean waitForStop) {
+        if (connection == null) {
+            return;
         }
-
-        setLink(null);
-        cancelTasks();
-
-        _resource.disconnected();
-
-        logger.info("Lost connection to host: {}. Attempting reconnection while we still have {} commands in progress.", _shell.getConnectedHost(), _inProgress.get());
-
-        _connection.stop();
-
+        connection.stop();
         try {
-            _connection.cleanUp();
+            connection.cleanUp();
         } catch (final IOException e) {
             logger.warn("Fail to clean up old connection. {}", e);
         }
-
-        while (_connection.isStartup()) {
-            _shell.getBackoffAlgorithm().waitBeforeRetry();
+        if (!waitForStop) {
+            return;
         }
+        do {
+            shell.getBackoffAlgorithm().waitBeforeRetry();
+        } while (connection.isStartup());
+    }
 
+    protected void reconnect(final Link link) {
+        if (!reconnectAllowed) {
+            logger.debug("Reconnect requested but it is not allowed {}", getLinkLog(link));
+            return;
+        }
+        cancelStartupTask();
+        closeAndTerminateLink(link);
+        closeAndTerminateLink(this.link);
+        setLink(null);
+        cancelTasks();
+        serverResource.disconnected();
+        logger.info("Lost connection to host: {}. Attempting reconnection while we still have {} commands in progress.", shell.getConnectedHost(), commandsInProgress.get());
+        stopAndCleanupConnection(true);
         do {
-            final String host = _shell.getNextHost();
-            _connection = new NioClient("Agent", host, _shell.getPort(), _shell.getWorkers(), this);
-            logger.info("Reconnecting to host:{}", host);
+            final String host = shell.getNextHost();
+            connection = new NioClient(getAgentName(), host, shell.getPort(), shell.getWorkers(), shell.getSslHandshakeTimeout(), this);
+            logger.info("Reconnecting to host: {}", host);
             try {
-                _connection.start();
+                connection.start();
             } catch (final NioConnectionException e) {
                 logger.info("Attempted to re-connect to the server, but received an unexpected exception, trying again...", e);
-                _connection.stop();
-                try {
-                    _connection.cleanUp();
-                } catch (final IOException ex) {
-                    logger.warn("Fail to clean up old connection. {}", ex);
-                }
+                stopAndCleanupConnection(false);
             }
-            _shell.getBackoffAlgorithm().waitBeforeRetry();
-        } while (!_connection.isStartup());
-        _shell.updateConnectedHost();
-        logger.info("Connected to the host: {}", _shell.getConnectedHost());
+            shell.getBackoffAlgorithm().waitBeforeRetry();
+        } while (!connection.isStartup());
+        shell.updateConnectedHost();
+        logger.info("Connected to the host: {}", shell.getConnectedHost());
     }
 
     public void processStartupAnswer(final Answer answer, final Response response, final Link link) {
-        boolean cancelled = false;
-        synchronized (this) {
-            if (_startup != null) {
-                _startup.cancel();
-                _startup = null;
-            } else {
-                cancelled = true;
-            }
-        }
+        boolean answerValid = cancelStartupTask();
         final StartupAnswer startup = (StartupAnswer)answer;
         if (!startup.getResult()) {
             logger.error("Not allowed to connect to the server: {}", answer.getDetails());
+            if (serverResource != null && !serverResource.isExitOnFailures()) {
+                logger.trace("{} does not allow exit on failure, reconnecting",
+                        serverResource.getClass().getSimpleName());
+                reconnect(link);
+                return;
+            }
             System.exit(1);
         }
-        if (cancelled) {
+        if (!answerValid) {
             logger.warn("Threw away a startup answer because we're reconnecting.");
             return;
         }
@@ -597,12 +644,12 @@ public void processStartupAnswer(final Answer answer, final Response response, f
         logger.info("Process agent startup answer, agent id = {}", startup.getHostId());
 
         setId(startup.getHostId());
-        _pingInterval = (long)startup.getPingInterval() * 1000; // change to ms.
+        pingInterval = startup.getPingInterval() * 1000L; // change to ms.
 
-        setLastPingResponseTime();
-        scheduleWatch(link, response, _pingInterval, _pingInterval);
+        updateLastPingResponseTime();
+        scheduleWatch(link, response, pingInterval, pingInterval);
 
-        _ugentTaskPool.setKeepAliveTime(2 * _pingInterval, TimeUnit.MILLISECONDS);
+        outRequestHandler.setKeepAliveTime(2 * pingInterval, TimeUnit.MILLISECONDS);
 
         logger.info("Startup Response Received: agent id = {}", getId());
     }
@@ -618,9 +665,6 @@ protected void processRequest(final Request request, final Link link) {
                 final Command cmd = cmds[i];
                 Answer answer;
                 try {
-                    if (cmd.getContextParam("logid") != null) {
-                        ThreadContext.put("logcontextid", cmd.getContextParam("logid"));
-                    }
                     if (logger.isDebugEnabled()) {
                         if (!requestLogged) // ensures request is logged only once per method call
                         {
@@ -635,7 +679,7 @@ protected void processRequest(final Request request, final Link link) {
 
                     if (cmd instanceof CronCommand) {
                         final CronCommand watch = (CronCommand)cmd;
-                        scheduleWatch(link, request, (long)watch.getInterval() * 1000, watch.getInterval() * 1000);
+                        scheduleWatch(link, request, watch.getInterval() * 1000L, watch.getInterval() * 1000L);
                         answer = new Answer(cmd, true, null);
                     } else if (cmd instanceof ShutdownCommand) {
                         final ShutdownCommand shutdown = (ShutdownCommand)cmd;
@@ -644,10 +688,17 @@ protected void processRequest(final Request request, final Link link) {
                         if (shutdown.isRemoveHost()) {
                             cleanupAgentZoneProperties();
                         }
-                        _reconnectAllowed = false;
+                        reconnectAllowed = false;
                         answer = new Answer(cmd, true, null);
                     } else if (cmd instanceof ReadyCommand && ((ReadyCommand)cmd).getDetails() != null) {
+
                         logger.debug("Not ready to connect to mgt server: {}", ((ReadyCommand)cmd).getDetails());
+                        if (serverResource != null && !serverResource.isExitOnFailures()) {
+                            logger.trace("{} does not allow exit on failure, reconnecting",
+                                    serverResource.getClass().getSimpleName());
+                            reconnect(link);
+                            return;
+                        }
                         System.exit(1);
                         return;
                     } else if (cmd instanceof MaintainCommand) {
@@ -655,12 +706,10 @@ protected void processRequest(final Request request, final Link link) {
                         answer = new MaintainAnswer((MaintainCommand)cmd);
                     } else if (cmd instanceof AgentControlCommand) {
                         answer = null;
-                        synchronized (_controlListeners) {
-                            for (final IAgentControlListener listener : _controlListeners) {
-                                answer = listener.processControlRequest(request, (AgentControlCommand)cmd);
-                                if (answer != null) {
-                                    break;
-                                }
+                        for (final IAgentControlListener listener : controlListeners) {
+                            answer = listener.processControlRequest(request, (AgentControlCommand)cmd);
+                            if (answer != null) {
+                                break;
                             }
                         }
 
@@ -672,8 +721,8 @@ protected void processRequest(final Request request, final Link link) {
                         answer = setupAgentKeystore((SetupKeyStoreCommand) cmd);
                     } else if (cmd instanceof SetupCertificateCommand && ((SetupCertificateCommand) cmd).isHandleByAgent()) {
                         answer = setupAgentCertificate((SetupCertificateCommand) cmd);
-                        if (Host.Type.Routing.equals(_resource.getType())) {
-                            scheduleServicesRestartTask();
+                        if (Host.Type.Routing.equals(serverResource.getType())) {
+                            scheduleCertificateRenewalTask();
                         }
                     } else if (cmd instanceof SetupMSListCommand) {
                         answer = setupManagementServerList((SetupMSListCommand) cmd);
@@ -681,11 +730,11 @@ protected void processRequest(final Request request, final Link link) {
                         if (cmd instanceof ReadyCommand) {
                             processReadyCommand(cmd);
                         }
-                        _inProgress.incrementAndGet();
+                        commandsInProgress.incrementAndGet();
                         try {
-                            answer = _resource.executeRequest(cmd);
+                            answer = serverResource.executeRequest(cmd);
                         } finally {
-                            _inProgress.decrementAndGet();
+                            commandsInProgress.decrementAndGet();
                         }
                         if (answer == null) {
                             logger.debug("Response: unsupported command {}", cmd.toString());
@@ -739,13 +788,13 @@ public Answer setupAgentKeystore(final SetupKeyStoreCommand cmd) {
         final String keyStoreFile = agentFile.getParent() + "/" + KeyStoreUtils.KS_FILENAME;
         final String csrFile = agentFile.getParent() + "/" + KeyStoreUtils.CSR_FILENAME;
 
-        String storedPassword = _shell.getPersistentProperty(null, KeyStoreUtils.KS_PASSPHRASE_PROPERTY);
+        String storedPassword = shell.getPersistentProperty(null, KeyStoreUtils.KS_PASSPHRASE_PROPERTY);
         if (StringUtils.isEmpty(storedPassword)) {
             storedPassword = keyStorePassword;
-            _shell.setPersistentProperty(null, KeyStoreUtils.KS_PASSPHRASE_PROPERTY, storedPassword);
+            shell.setPersistentProperty(null, KeyStoreUtils.KS_PASSPHRASE_PROPERTY, storedPassword);
         }
 
-        Script script = new Script(_keystoreSetupPath, 300000, logger);
+        Script script = new Script(keystoreSetupSetupPath, 300000, logger);
         script.add(agentFile.getAbsolutePath());
         script.add(keyStoreFile);
         script.add(storedPassword);
@@ -789,8 +838,8 @@ private Answer setupAgentCertificate(final SetupCertificateCommand cmd) {
             throw new CloudRuntimeException("Unable to save received agent client and ca certificates", e);
         }
 
-        String ksPassphrase = _shell.getPersistentProperty(null, KeyStoreUtils.KS_PASSPHRASE_PROPERTY);
-        Script script = new Script(_keystoreCertImportPath, 300000, logger);
+        String ksPassphrase = shell.getPersistentProperty(null, KeyStoreUtils.KS_PASSPHRASE_PROPERTY);
+        Script script = new Script(keystoreCertImportScriptPath, 300000, logger);
         script.add(agentFile.getAbsolutePath());
         script.add(ksPassphrase);
         script.add(keyStoreFile);
@@ -812,9 +861,9 @@ private void processManagementServerList(final List<String> msList, final String
         if (CollectionUtils.isNotEmpty(msList) && StringUtils.isNotEmpty(lbAlgorithm)) {
             try {
                 final String newMSHosts = String.format("%s%s%s", com.cloud.utils.StringUtils.toCSVList(msList), IAgentShell.hostLbAlgorithmSeparator, lbAlgorithm);
-                _shell.setPersistentProperty(null, "host", newMSHosts);
-                _shell.setHosts(newMSHosts);
-                _shell.resetHostCounter();
+                shell.setPersistentProperty(null, "host", newMSHosts);
+                shell.setHosts(newMSHosts);
+                shell.resetHostCounter();
                 logger.info("Processed new management server list: {}", newMSHosts);
             } catch (final Exception e) {
                 throw new CloudRuntimeException("Could not persist received management servers list", e);
@@ -823,7 +872,7 @@ private void processManagementServerList(final List<String> msList, final String
         if ("shuffle".equals(lbAlgorithm)) {
             scheduleHostLBCheckerTask(0);
         } else {
-            scheduleHostLBCheckerTask(_shell.getLbCheckerInterval(lbCheckInterval));
+            scheduleHostLBCheckerTask(shell.getLbCheckerInterval(lbCheckInterval));
         }
     }
 
@@ -839,16 +888,14 @@ public void processResponse(final Response response, final Link link) {
             processStartupAnswer(answer, response, link);
         } else if (answer instanceof AgentControlAnswer) {
             // Notice, we are doing callback while holding a lock!
-            synchronized (_controlListeners) {
-                for (final IAgentControlListener listener : _controlListeners) {
-                    listener.processControlResponse(response, (AgentControlAnswer)answer);
-                }
+            for (final IAgentControlListener listener : controlListeners) {
+                listener.processControlResponse(response, (AgentControlAnswer)answer);
             }
-        } else if (answer instanceof PingAnswer && (((PingAnswer) answer).isSendStartup()) && _reconnectAllowed) {
+        } else if (answer instanceof PingAnswer && (((PingAnswer) answer).isSendStartup()) && reconnectAllowed) {
             logger.info("Management server requested startup command to reinitialize the agent");
             sendStartup(link);
         } else {
-            setLastPingResponseTime();
+            updateLastPingResponseTime();
         }
     }
 
@@ -883,22 +930,24 @@ private void verifyAgentArch(String arch) {
     public void processOtherTask(final Task task) {
         final Object obj = task.get();
         if (obj instanceof Response) {
-            if (System.currentTimeMillis() - _lastPingResponseTime > _pingInterval * _shell.getPingRetries()) {
-                logger.error("Ping Interval has gone past {}. Won't reconnect to mgt server, as connection is still alive", _pingInterval * _shell.getPingRetries());
+            if (System.currentTimeMillis() - lastPingResponseTime.get() > pingInterval * shell.getPingRetries()) {
+                logger.error("Ping Interval has gone past {}. Won't reconnect to mgt server, as connection is still alive",
+                        pingInterval * shell.getPingRetries());
                 return;
             }
 
-            final PingCommand ping = _resource.getCurrentStatus(getId());
-            final Request request = new Request(_id, -1, ping, false);
+            final PingCommand ping = serverResource.getCurrentStatus(getId());
+            final Request request = new Request(id, -1, ping, false);
             request.setSequence(getNextSequence());
             logger.debug("Sending ping: {}", request.toString());
 
             try {
                 task.getLink().send(request.toBytes());
                 //if i can send pingcommand out, means the link is ok
-                setLastPingResponseTime();
+                updateLastPingResponseTime();
             } catch (final ClosedChannelException e) {
-                logger.warn("Unable to send request: {}", request.toString());
+                logger.warn("Unable to send request to {} due to '{}', request: {}",
+                        getLinkLog(task.getLink()), e.getMessage(), request);
             }
 
         } else if (obj instanceof Request) {
@@ -908,11 +957,11 @@ public void processOtherTask(final Task task) {
                 ThreadContext.put("logcontextid", command.getContextParam("logid"));
             }
             Answer answer = null;
-            _inProgress.incrementAndGet();
+            commandsInProgress.incrementAndGet();
             try {
-                answer = _resource.executeRequest(command);
+                answer = serverResource.executeRequest(command);
             } finally {
-                _inProgress.decrementAndGet();
+                commandsInProgress.decrementAndGet();
             }
             if (answer != null) {
                 final Response response = new Response(req, answer);
@@ -929,46 +978,37 @@ public void processOtherTask(final Task task) {
         }
     }
 
-    public synchronized void setLastPingResponseTime() {
-        _lastPingResponseTime = System.currentTimeMillis();
+    public void updateLastPingResponseTime() {
+        lastPingResponseTime.set(System.currentTimeMillis());
     }
 
-    protected synchronized long getNextSequence() {
-        return _sequence++;
+    protected long getNextSequence() {
+        return sequence.getAndIncrement();
     }
 
     @Override
     public void registerControlListener(final IAgentControlListener listener) {
-        synchronized (_controlListeners) {
-            _controlListeners.add(listener);
-        }
+        controlListeners.add(listener);
     }
 
     @Override
     public void unregisterControlListener(final IAgentControlListener listener) {
-        synchronized (_controlListeners) {
-            _controlListeners.remove(listener);
-        }
+        controlListeners.remove(listener);
     }
 
     @Override
     public AgentControlAnswer sendRequest(final AgentControlCommand cmd, final int timeoutInMilliseconds) throws AgentControlChannelException {
         final Request request = new Request(getId(), -1, new Command[] {cmd}, true, false);
         request.setSequence(getNextSequence());
-
         final AgentControlListener listener = new AgentControlListener(request);
-
         registerControlListener(listener);
         try {
             postRequest(request);
-            synchronized (listener) {
-                try {
-                    listener.wait(timeoutInMilliseconds);
-                } catch (final InterruptedException e) {
-                    logger.warn("sendRequest is interrupted, exit waiting");
-                }
+            try {
+                listener.wait(timeoutInMilliseconds);
+            } catch (final InterruptedException e) {
+                logger.warn("sendRequest is interrupted, exit waiting");
             }
-
             return listener.getAnswer();
         } finally {
             unregisterControlListener(listener);
@@ -983,9 +1023,9 @@ public void postRequest(final AgentControlCommand cmd) throws AgentControlChanne
     }
 
     private void postRequest(final Request request) throws AgentControlChannelException {
-        if (_link != null) {
+        if (link != null) {
             try {
-                _link.send(request.toBytes());
+                link.send(request.toBytes());
             } catch (final ClosedChannelException e) {
                 logger.warn("Unable to post agent control request: {}", request.toString());
                 throw new AgentControlChannelException("Unable to post agent control request due to " + e.getMessage());
@@ -1037,7 +1077,7 @@ public void run() {
         }
     }
 
-    public class WatchTask extends ManagedContextTimerTask {
+    public class WatchTask implements Runnable {
         protected Request _request;
         protected Agent _agent;
         protected Link _link;
@@ -1050,11 +1090,11 @@ public WatchTask(final Link link, final Request request, final Agent agent) {
         }
 
         @Override
-        protected void runInContext() {
+        public void run() {
             logger.trace("Scheduling {}", (_request instanceof Response ? "Ping" : "Watch Task"));
             try {
                 if (_request instanceof Response) {
-                    _ugentTaskPool.submit(new ServerHandler(Task.Type.OTHER, _link, _request));
+                    outRequestHandler.submit(new ServerHandler(Task.Type.OTHER, _link, _request));
                 } else {
                     _link.schedule(new ServerHandler(Task.Type.OTHER, _link, _request));
                 }
@@ -1064,34 +1104,33 @@ protected void runInContext() {
         }
     }
 
-    public class StartupTask extends ManagedContextTimerTask {
+    public class StartupTask implements Runnable {
         protected Link _link;
-        protected volatile boolean cancelled = false;
+        private final AtomicBoolean cancelled = new AtomicBoolean(false);
 
         public StartupTask(final Link link) {
             logger.debug("Startup task created");
             _link = link;
         }
 
-        @Override
-        public synchronized boolean cancel() {
+        public boolean cancel() {
             // TimerTask.cancel may fail depends on the calling context
-            if (!cancelled) {
-                cancelled = true;
-                _startupWait = _startupWaitDefault;
+            if (cancelled.compareAndSet(false, true)) {
+                startupWait = DEFAULT_STARTUP_WAIT;
                 logger.debug("Startup task cancelled");
-                return super.cancel();
             }
             return true;
         }
 
         @Override
-        protected synchronized void runInContext() {
-            if (!cancelled) {
-                logger.info("The startup command is now cancelled");
-                cancelled = true;
-                _startup = null;
-                _startupWait = _startupWaitDefault * 2;
+        public void run() {
+            if (cancelled.compareAndSet(false, true)) {
+                logger.info("The running startup command is now invalid. Attempting reconnect");
+                startupTask.set(null);
+                startupWait = DEFAULT_STARTUP_WAIT * 2;
+                if (logger.isDebugEnabled()) {
+                    logger.debug("Executing reconnect from task - {}", getLinkLog(_link));
+                }
                 reconnect(_link);
             }
         }
@@ -1123,7 +1162,7 @@ public ServerHandler(final Task.Type type, final Link link, final Request req) {
         @Override
         public void doTask(final Task task) throws TaskExecutionException {
             if (task.getType() == Task.Type.CONNECT) {
-                _shell.getBackoffAlgorithm().reset();
+                shell.getBackoffAlgorithm().reset();
                 setLink(task.getLink());
                 sendStartup(task.getLink());
             } else if (task.getType() == Task.Type.DATA) {
@@ -1136,7 +1175,7 @@ public void doTask(final Task task) throws TaskExecutionException {
                     } else {
                         //put the requests from mgt server into another thread pool, as the request may take a longer time to finish. Don't block the NIO main thread pool
                         //processRequest(request, task.getLink());
-                        _executor.submit(new AgentRequestHandler(getType(), getLink(), request));
+                        requestHandler.submit(new AgentRequestHandler(getType(), getLink(), request));
                     }
                 } catch (final ClassNotFoundException e) {
                     logger.error("Unable to find this request ");
@@ -1144,14 +1183,8 @@ public void doTask(final Task task) throws TaskExecutionException {
                     logger.error("Error parsing task", e);
                 }
             } else if (task.getType() == Task.Type.DISCONNECT) {
-                try {
-                    // an issue has been found if reconnect immediately after disconnecting. please refer to https://github.com/apache/cloudstack/issues/8517
-                    // wait 5 seconds before reconnecting
-                    Thread.sleep(5000);
-                } catch (InterruptedException e) {
-                }
+                logger.debug("Executing disconnect task - {}", getLinkLog(task.getLink()));
                 reconnect(task.getLink());
-                return;
             } else if (task.getType() == Task.Type.OTHER) {
                 processOtherTask(task);
             }
@@ -1174,26 +1207,25 @@ public PostCertificateRenewalTask(final Agent agent) {
         protected void runInContext() {
             while (true) {
                 try {
-                    if (_inProgress.get() == 0) {
+                    if (commandsInProgress.get() == 0) {
                         logger.debug("Running post certificate renewal task to restart services.");
 
                         // Let the resource perform any post certificate renewal cleanups
-                        _resource.executeRequest(new PostCertificateRenewalCommand());
+                        serverResource.executeRequest(new PostCertificateRenewalCommand());
 
-                        IAgentShell shell = agent._shell;
-                        ServerResource resource = agent._resource.getClass().newInstance();
+                        IAgentShell shell = agent.shell;
+                        ServerResource resource = agent.serverResource.getClass().getDeclaredConstructor().newInstance();
 
                         // Stop current agent
                         agent.cancelTasks();
-                        agent._reconnectAllowed = false;
-                        Runtime.getRuntime().removeShutdownHook(agent._shutdownThread);
+                        agent.reconnectAllowed = false;
+                        Runtime.getRuntime().removeShutdownHook(agent.shutdownThread);
                         agent.stop(ShutdownCommand.Requested, "Restarting due to new X509 certificates");
 
                         // Nullify references for GC
-                        agent._shell = null;
-                        agent._watchList = null;
-                        agent._shutdownThread = null;
-                        agent._controlListeners = null;
+                        agent.watchList = null;
+                        agent.shutdownThread = null;
+                        agent.controlListeners = null;
                         agent = null;
 
                         // Start a new agent instance
@@ -1201,7 +1233,6 @@ protected void runInContext() {
                         return;
                     }
                     logger.debug("Other tasks are in progress, will retry post certificate renewal command after few seconds");
-
                     Thread.sleep(5000);
                 } catch (final Exception e) {
                     logger.warn("Failed to execute post certificate renewal command:", e);
@@ -1216,35 +1247,34 @@ public class PreferredHostCheckerTask extends ManagedContextTimerTask {
         @Override
         protected void runInContext() {
             try {
-                final String[] msList = _shell.getHosts();
+                final String[] msList = shell.getHosts();
                 if (msList == null || msList.length < 1) {
                     return;
                 }
                 final String preferredHost  = msList[0];
-                final String connectedHost = _shell.getConnectedHost();
-                logger.trace("Running preferred host checker task, connected host={}, preferred host={}", connectedHost, preferredHost);
-
-                if (preferredHost != null && !preferredHost.equals(connectedHost) && _link != null) {
-                    boolean isHostUp = true;
-                    try (final Socket socket = new Socket()) {
-                        socket.connect(new InetSocketAddress(preferredHost, _shell.getPort()), 5000);
-                    } catch (final IOException e) {
-                        isHostUp = false;
-                        logger.trace("Host: {} is not reachable", preferredHost);
-
-                    }
-                    if (isHostUp && _link != null && _inProgress.get() == 0) {
+                final String connectedHost = shell.getConnectedHost();
+                logger.debug("Running preferred host checker task, connected host={}, preferred host={}",
+                        connectedHost, preferredHost);
+                if (preferredHost == null || preferredHost.equals(connectedHost) || link == null) {
+                    return;
+                }
+                boolean isHostUp = false;
+                try (final Socket socket = new Socket()) {
+                    socket.connect(new InetSocketAddress(preferredHost, shell.getPort()), 5000);
+                    isHostUp = true;
+                } catch (final IOException e) {
+                    logger.debug("Host: {} is not reachable", preferredHost);
+                }
+                if (isHostUp && link != null && commandsInProgress.get() == 0) {
+                    if (logger.isDebugEnabled()) {
                         logger.debug("Preferred host {} is found to be reachable, trying to reconnect", preferredHost);
-
-                        _shell.resetHostCounter();
-                        reconnect(_link);
                     }
+                    shell.resetHostCounter();
+                    reconnect(link);
                 }
             } catch (Throwable t) {
                 logger.error("Error caught while attempting to connect to preferred host", t);
             }
         }
-
     }
-
 }
diff --git a/agent/src/main/java/com/cloud/agent/AgentShell.java b/agent/src/main/java/com/cloud/agent/AgentShell.java
index 0699e00250bb..c5257b95b7c2 100644
--- a/agent/src/main/java/com/cloud/agent/AgentShell.java
+++ b/agent/src/main/java/com/cloud/agent/AgentShell.java
@@ -16,29 +16,6 @@
 // under the License.
 package com.cloud.agent;
 
-import com.cloud.agent.Agent.ExitStatus;
-import com.cloud.agent.dao.StorageComponent;
-import com.cloud.agent.dao.impl.PropertiesStorage;
-import com.cloud.agent.properties.AgentProperties;
-import com.cloud.agent.properties.AgentPropertiesFileHandler;
-import com.cloud.resource.ServerResource;
-import com.cloud.utils.LogUtils;
-import com.cloud.utils.ProcessUtil;
-import com.cloud.utils.PropertiesUtil;
-import com.cloud.utils.backoff.BackoffAlgorithm;
-import com.cloud.utils.backoff.impl.ConstantTimeBackoff;
-import com.cloud.utils.exception.CloudRuntimeException;
-import org.apache.commons.daemon.Daemon;
-import org.apache.commons.daemon.DaemonContext;
-import org.apache.commons.daemon.DaemonInitException;
-import org.apache.commons.lang.math.NumberUtils;
-import org.apache.commons.lang3.BooleanUtils;
-import org.apache.commons.lang3.StringUtils;
-import org.apache.logging.log4j.Logger;
-import org.apache.logging.log4j.LogManager;
-import org.apache.logging.log4j.core.config.Configurator;
-
-import javax.naming.ConfigurationException;
 import java.io.File;
 import java.io.FileNotFoundException;
 import java.io.IOException;
@@ -53,6 +30,31 @@
 import java.util.Properties;
 import java.util.UUID;
 
+import javax.naming.ConfigurationException;
+
+import org.apache.commons.daemon.Daemon;
+import org.apache.commons.daemon.DaemonContext;
+import org.apache.commons.daemon.DaemonInitException;
+import org.apache.commons.lang.math.NumberUtils;
+import org.apache.commons.lang3.BooleanUtils;
+import org.apache.commons.lang3.StringUtils;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+import org.apache.logging.log4j.core.config.Configurator;
+
+import com.cloud.agent.Agent.ExitStatus;
+import com.cloud.agent.dao.StorageComponent;
+import com.cloud.agent.dao.impl.PropertiesStorage;
+import com.cloud.agent.properties.AgentProperties;
+import com.cloud.agent.properties.AgentPropertiesFileHandler;
+import com.cloud.resource.ServerResource;
+import com.cloud.utils.LogUtils;
+import com.cloud.utils.ProcessUtil;
+import com.cloud.utils.PropertiesUtil;
+import com.cloud.utils.backoff.BackoffAlgorithm;
+import com.cloud.utils.backoff.impl.ConstantTimeBackoff;
+import com.cloud.utils.exception.CloudRuntimeException;
+
 public class AgentShell implements IAgentShell, Daemon {
     protected static Logger LOGGER = LogManager.getLogger(AgentShell.class);
 
@@ -406,7 +408,9 @@ public void init(String[] args) throws ConfigurationException {
 
         LOGGER.info("Defaulting to the constant time backoff algorithm");
         _backoff = new ConstantTimeBackoff();
-        _backoff.configure("ConstantTimeBackoff", new HashMap<String, Object>());
+        Map<String, Object> map = new HashMap<>();
+        map.put("seconds", _properties.getProperty("backoff.seconds"));
+        _backoff.configure("ConstantTimeBackoff", map);
     }
 
     private void launchAgent() throws ConfigurationException {
@@ -455,6 +459,11 @@ public void launchNewAgent(ServerResource resource) throws ConfigurationExceptio
         agent.start();
     }
 
+    @Override
+    public Integer getSslHandshakeTimeout() {
+        return AgentPropertiesFileHandler.getPropertyValue(AgentProperties.SSL_HANDSHAKE_TIMEOUT);
+    }
+
     public synchronized int getNextAgentId() {
         return _nextAgentId++;
     }
diff --git a/agent/src/main/java/com/cloud/agent/IAgentShell.java b/agent/src/main/java/com/cloud/agent/IAgentShell.java
index 2dd08fffd459..7f04048795d7 100644
--- a/agent/src/main/java/com/cloud/agent/IAgentShell.java
+++ b/agent/src/main/java/com/cloud/agent/IAgentShell.java
@@ -70,4 +70,6 @@ public interface IAgentShell {
     String getConnectedHost();
 
     void launchNewAgent(ServerResource resource) throws ConfigurationException;
+
+    Integer getSslHandshakeTimeout();
 }
diff --git a/agent/src/main/java/com/cloud/agent/properties/AgentProperties.java b/agent/src/main/java/com/cloud/agent/properties/AgentProperties.java
index 8f97edc39357..2efe24e655d5 100644
--- a/agent/src/main/java/com/cloud/agent/properties/AgentProperties.java
+++ b/agent/src/main/java/com/cloud/agent/properties/AgentProperties.java
@@ -810,6 +810,13 @@ public Property<Integer> getWorkers() {
      */
     public static final Property<String> HOST_TAGS = new Property<>("host.tags", null, String.class);
 
+    /**
+     * Timeout for SSL handshake in seconds
+     * Data type: Integer.<br>
+     * Default value: <code>null</code>
+     */
+    public static final Property<Integer> SSL_HANDSHAKE_TIMEOUT = new Property<>("ssl.handshake.timeout", null, Integer.class);
+
     public static class Property <T>{
         private String name;
         private T defaultValue;
diff --git a/api/src/main/java/org/apache/cloudstack/acl/RoleService.java b/api/src/main/java/org/apache/cloudstack/acl/RoleService.java
index 68204d432534..f041c8342aec 100644
--- a/api/src/main/java/org/apache/cloudstack/acl/RoleService.java
+++ b/api/src/main/java/org/apache/cloudstack/acl/RoleService.java
@@ -30,6 +30,11 @@ public interface RoleService {
     ConfigKey<Boolean> EnableDynamicApiChecker = new ConfigKey<>("Advanced", Boolean.class, "dynamic.apichecker.enabled", "false",
             "If set to true, this enables the dynamic role-based api access checker and disables the default static role-based api access checker.", true);
 
+    ConfigKey<Integer> DynamicApiCheckerCachePeriod = new ConfigKey<>("Advanced", Integer.class,
+            "dynamic.apichecker.cache.period", "0",
+            "Defines the expiration time in seconds for the Dynamic API Checker cache, determining how long cached data is retained before being refreshed. If set to zero then caching will be disabled",
+            false);
+
     boolean isEnabled();
 
     /**
diff --git a/api/src/main/java/org/apache/cloudstack/api/command/admin/domain/ListDomainsCmd.java b/api/src/main/java/org/apache/cloudstack/api/command/admin/domain/ListDomainsCmd.java
index b91e56dcaef0..895e93289923 100644
--- a/api/src/main/java/org/apache/cloudstack/api/command/admin/domain/ListDomainsCmd.java
+++ b/api/src/main/java/org/apache/cloudstack/api/command/admin/domain/ListDomainsCmd.java
@@ -100,7 +100,7 @@ public EnumSet<DomainDetails> getDetails() throws InvalidParameterValueException
             dv = EnumSet.of(DomainDetails.all);
         } else {
             try {
-                ArrayList<DomainDetails> dc = new ArrayList<DomainDetails>();
+                ArrayList<DomainDetails> dc = new ArrayList<>();
                 for (String detail : viewDetails) {
                     dc.add(DomainDetails.valueOf(detail));
                 }
@@ -142,7 +142,10 @@ protected void updateDomainResponse(List<DomainResponse> response) {
         if (CollectionUtils.isEmpty(response)) {
             return;
         }
-        _resourceLimitService.updateTaggedResourceLimitsAndCountsForDomains(response, getTag());
+        EnumSet<DomainDetails> details = getDetails();
+        if (details.contains(DomainDetails.all) || details.contains(DomainDetails.resource)) {
+            _resourceLimitService.updateTaggedResourceLimitsAndCountsForDomains(response, getTag());
+        }
         if (!getShowIcon()) {
             return;
         }
diff --git a/api/src/main/java/org/apache/cloudstack/api/command/user/account/ListAccountsCmd.java b/api/src/main/java/org/apache/cloudstack/api/command/user/account/ListAccountsCmd.java
index 0a962b19e4f3..8cfb4d8406b4 100644
--- a/api/src/main/java/org/apache/cloudstack/api/command/user/account/ListAccountsCmd.java
+++ b/api/src/main/java/org/apache/cloudstack/api/command/user/account/ListAccountsCmd.java
@@ -149,7 +149,10 @@ protected void updateAccountResponse(List<AccountResponse> response) {
         if (CollectionUtils.isEmpty(response)) {
             return;
         }
-        _resourceLimitService.updateTaggedResourceLimitsAndCountsForAccounts(response, getTag());
+        EnumSet<DomainDetails> details = getDetails();
+        if (details.contains(DomainDetails.all) || details.contains(DomainDetails.resource)) {
+            _resourceLimitService.updateTaggedResourceLimitsAndCountsForAccounts(response, getTag());
+        }
         if (!getShowIcon()) {
             return;
         }
diff --git a/api/src/main/java/org/apache/cloudstack/outofbandmanagement/OutOfBandManagementService.java b/api/src/main/java/org/apache/cloudstack/outofbandmanagement/OutOfBandManagementService.java
index d670e4d3a88f..4f6f1ad66c93 100644
--- a/api/src/main/java/org/apache/cloudstack/outofbandmanagement/OutOfBandManagementService.java
+++ b/api/src/main/java/org/apache/cloudstack/outofbandmanagement/OutOfBandManagementService.java
@@ -39,7 +39,7 @@ public interface OutOfBandManagementService {
     long getId();
     boolean isOutOfBandManagementEnabled(Host host);
     void submitBackgroundPowerSyncTask(Host host);
-    boolean transitionPowerStateToDisabled(List<? extends Host> hosts);
+    boolean transitionPowerStateToDisabled(List<Long> hostIds);
 
     OutOfBandManagementResponse enableOutOfBandManagement(DataCenter zone);
     OutOfBandManagementResponse enableOutOfBandManagement(Cluster cluster);
diff --git a/core/src/main/java/com/cloud/agent/api/CheckNetworkCommand.java b/core/src/main/java/com/cloud/agent/api/CheckNetworkCommand.java
index 717af2afa06c..cb5416904257 100644
--- a/core/src/main/java/com/cloud/agent/api/CheckNetworkCommand.java
+++ b/core/src/main/java/com/cloud/agent/api/CheckNetworkCommand.java
@@ -29,6 +29,7 @@ public class CheckNetworkCommand extends Command {
 
     public CheckNetworkCommand(List<PhysicalNetworkSetupInfo> networkInfoList) {
         this.networkInfoList = networkInfoList;
+        setWait(120);
     }
 
     public List<PhysicalNetworkSetupInfo> getPhysicalNetworkInfoList() {
diff --git a/core/src/main/java/com/cloud/resource/ServerResource.java b/core/src/main/java/com/cloud/resource/ServerResource.java
index 1602a78d9a47..092019e7f21b 100644
--- a/core/src/main/java/com/cloud/resource/ServerResource.java
+++ b/core/src/main/java/com/cloud/resource/ServerResource.java
@@ -78,4 +78,12 @@ public interface ServerResource extends Manager {
 
     void setAgentControl(IAgentControl agentControl);
 
+    default boolean isExitOnFailures() {
+        return true;
+    }
+
+    default boolean isAppendAgentNameToLogs() {
+        return false;
+    }
+
 }
diff --git a/engine/api/src/main/java/com/cloud/vm/VirtualMachineManager.java b/engine/api/src/main/java/com/cloud/vm/VirtualMachineManager.java
index e8ffd86ac4f1..94c73d8f4d60 100644
--- a/engine/api/src/main/java/com/cloud/vm/VirtualMachineManager.java
+++ b/engine/api/src/main/java/com/cloud/vm/VirtualMachineManager.java
@@ -22,7 +22,6 @@
 import java.util.List;
 import java.util.Map;
 
-import com.cloud.exception.ResourceAllocationException;
 import org.apache.cloudstack.context.CallContext;
 import org.apache.cloudstack.framework.config.ConfigKey;
 
@@ -38,6 +37,7 @@
 import com.cloud.exception.InsufficientCapacityException;
 import com.cloud.exception.InsufficientServerCapacityException;
 import com.cloud.exception.OperationTimedoutException;
+import com.cloud.exception.ResourceAllocationException;
 import com.cloud.exception.ResourceUnavailableException;
 import com.cloud.host.Host;
 import com.cloud.hypervisor.Hypervisor.HypervisorType;
@@ -101,6 +101,10 @@ public interface VirtualMachineManager extends Manager {
                     "refer documentation",
             true, ConfigKey.Scope.Zone);
 
+    ConfigKey<Boolean> VmSyncPowerStateTransitioning = new ConfigKey<>("Advanced", Boolean.class, "vm.sync.power.state.transitioning", "true",
+            "Whether to sync power states of the transitioning and stalled VMs while processing VM power reports.", false);
+
+
     interface Topics {
         String VM_POWER_STATE = "vm.powerstate";
     }
@@ -286,24 +290,22 @@ static String getHypervisorHostname(String name) {
 
     /**
      * Obtains statistics for a list of VMs; CPU and network utilization
-     * @param hostId ID of the host
-     * @param hostName name of the host
+     * @param host host
      * @param vmIds list of VM IDs
      * @return map of VM ID and stats entry for the VM
      */
-    HashMap<Long, ? extends VmStats> getVirtualMachineStatistics(long hostId, String hostName, List<Long> vmIds);
+    HashMap<Long, ? extends VmStats> getVirtualMachineStatistics(Host host, List<Long> vmIds);
     /**
      * Obtains statistics for a list of VMs; CPU and network utilization
-     * @param hostId ID of the host
-     * @param hostName name of the host
-     * @param vmMap map of VM IDs and the corresponding VirtualMachine object
+     * @param host host
+     * @param vmMap map of VM instanceName and its ID
      * @return map of VM ID and stats entry for the VM
      */
-    HashMap<Long, ? extends VmStats> getVirtualMachineStatistics(long hostId, String hostName, Map<Long, ? extends VirtualMachine> vmMap);
+    HashMap<Long, ? extends VmStats> getVirtualMachineStatistics(Host host, Map<String, Long> vmMap);
 
-    HashMap<Long, List<? extends VmDiskStats>> getVmDiskStatistics(long hostId, String hostName, Map<Long, ? extends VirtualMachine> vmMap);
+    HashMap<Long, List<? extends VmDiskStats>> getVmDiskStatistics(Host host, Map<String, Long> vmInstanceNameIdMap);
 
-    HashMap<Long, List<? extends VmNetworkStats>> getVmNetworkStatistics(long hostId, String hostName, Map<Long, ? extends VirtualMachine> vmMap);
+    HashMap<Long, List<? extends VmNetworkStats>> getVmNetworkStatistics(Host host, Map<String, Long> vmInstanceNameIdMap);
 
     Map<Long, Boolean> getDiskOfferingSuitabilityForVm(long vmId, List<Long> diskOfferingIds);
 
diff --git a/engine/components-api/src/main/java/com/cloud/capacity/CapacityManager.java b/engine/components-api/src/main/java/com/cloud/capacity/CapacityManager.java
index 1c3edad886bb..59f0679249cb 100644
--- a/engine/components-api/src/main/java/com/cloud/capacity/CapacityManager.java
+++ b/engine/components-api/src/main/java/com/cloud/capacity/CapacityManager.java
@@ -16,14 +16,11 @@
 // under the License.
 package com.cloud.capacity;
 
-import java.util.Map;
-
 import org.apache.cloudstack.framework.config.ConfigKey;
 import org.apache.cloudstack.storage.datastore.db.StoragePoolVO;
 
 import com.cloud.host.Host;
 import com.cloud.offering.ServiceOffering;
-import com.cloud.service.ServiceOfferingVO;
 import com.cloud.storage.VMTemplateVO;
 import com.cloud.utils.Pair;
 import com.cloud.vm.VirtualMachine;
@@ -118,6 +115,10 @@ public interface CapacityManager {
                     "Percentage (as a value between 0 and 1) of secondary storage capacity threshold.",
                     true);
 
+    ConfigKey<Integer> CapacityCalculateWorkers = new ConfigKey<>(ConfigKey.CATEGORY_ADVANCED, Integer.class,
+            "capacity.calculate.workers", "1",
+            "Number of worker threads to be used for capacities calculation", true);
+
     public boolean releaseVmCapacity(VirtualMachine vm, boolean moveFromReserved, boolean moveToReservered, Long hostId);
 
     void allocateVmCapacity(VirtualMachine vm, boolean fromLastHost);
@@ -133,8 +134,6 @@ boolean checkIfHostHasCapacity(long hostId, Integer cpu, long ram, boolean check
 
     void updateCapacityForHost(Host host);
 
-    void updateCapacityForHost(Host host, Map<Long, ServiceOfferingVO> offeringsMap);
-
     /**
      * @param pool storage pool
      * @param templateForVmCreation template that will be used for vm creation
@@ -151,12 +150,12 @@ boolean checkIfHostHasCapacity(long hostId, Integer cpu, long ram, boolean check
 
     /**
      * Check if specified host has capability to support cpu cores and speed freq
-     * @param hostId the host to be checked
+     * @param host the host to be checked
      * @param cpuNum cpu number to check
      * @param cpuSpeed cpu Speed to check
      * @return true if the count of host's running VMs >= hypervisor limit
      */
-    boolean checkIfHostHasCpuCapability(long hostId, Integer cpuNum, Integer cpuSpeed);
+    boolean checkIfHostHasCpuCapability(Host host, Integer cpuNum, Integer cpuSpeed);
 
     /**
      * Check if cluster will cross threshold if the cpu/memory requested are accommodated
diff --git a/engine/components-api/src/main/java/com/cloud/resource/ResourceManager.java b/engine/components-api/src/main/java/com/cloud/resource/ResourceManager.java
index b2ae8b898378..3b7e4e964e56 100755
--- a/engine/components-api/src/main/java/com/cloud/resource/ResourceManager.java
+++ b/engine/components-api/src/main/java/com/cloud/resource/ResourceManager.java
@@ -138,13 +138,13 @@ public interface ResourceManager extends ResourceService, Configurable {
 
     public List<HostVO> listAllHostsInOneZoneNotInClusterByHypervisors(List<HypervisorType> types, long dcId, long clusterId);
 
-    public List<HypervisorType> listAvailHypervisorInZone(Long hostId, Long zoneId);
+    public List<HypervisorType> listAvailHypervisorInZone(Long zoneId);
 
     public HostVO findHostByGuid(String guid);
 
     public HostVO findHostByName(String name);
 
-    HostStats getHostStatistics(long hostId);
+    HostStats getHostStatistics(Host host);
 
     Long getGuestOSCategoryId(long hostId);
 
diff --git a/engine/components-api/src/main/java/com/cloud/storage/StorageManager.java b/engine/components-api/src/main/java/com/cloud/storage/StorageManager.java
index c3909bc56b0d..cf48d75bd1e5 100644
--- a/engine/components-api/src/main/java/com/cloud/storage/StorageManager.java
+++ b/engine/components-api/src/main/java/com/cloud/storage/StorageManager.java
@@ -22,6 +22,7 @@
 
 import org.apache.cloudstack.engine.subsystem.api.storage.DataStore;
 import org.apache.cloudstack.engine.subsystem.api.storage.HypervisorHostListener;
+import org.apache.cloudstack.engine.subsystem.api.storage.Scope;
 import org.apache.cloudstack.framework.config.ConfigKey;
 import org.apache.cloudstack.storage.datastore.db.StoragePoolVO;
 
@@ -42,6 +43,7 @@
 import com.cloud.offering.ServiceOffering;
 import com.cloud.storage.Storage.ImageFormat;
 import com.cloud.utils.Pair;
+import com.cloud.utils.exception.CloudRuntimeException;
 import com.cloud.vm.DiskProfile;
 import com.cloud.vm.VMInstanceVO;
 
@@ -209,6 +211,10 @@ public interface StorageManager extends StorageService {
     ConfigKey<Long> HEURISTICS_SCRIPT_TIMEOUT = new ConfigKey<>("Advanced", Long.class, "heuristics.script.timeout", "3000",
             "The maximum runtime, in milliseconds, to execute the heuristic rule; if it is reached, a timeout will happen.", true);
 
+    ConfigKey<Integer> StoragePoolHostConnectWorkers = new ConfigKey<>("Storage", Integer.class,
+            "storage.pool.host.connect.workers", "1",
+            "Number of worker threads to be used to connect hosts to a primary storage", true);
+
     /**
      * should we execute in sequence not involving any storages?
      * @return tru if commands should execute in sequence
@@ -360,6 +366,9 @@ static Boolean getFullCloneConfiguration(Long storeId) {
 
     String getStoragePoolMountFailureReason(String error);
 
+    void connectHostsToPool(DataStore primaryStore, List<Long> hostIds, Scope scope,
+            boolean handleStorageConflictException, boolean errorOnNoUpHost) throws CloudRuntimeException;
+
     boolean connectHostToSharedPool(long hostId, long poolId) throws StorageUnavailableException, StorageConflictException;
 
     void disconnectHostFromSharedPool(long hostId, long poolId) throws StorageUnavailableException, StorageConflictException;
diff --git a/engine/orchestration/src/main/java/com/cloud/agent/manager/AgentManagerImpl.java b/engine/orchestration/src/main/java/com/cloud/agent/manager/AgentManagerImpl.java
index 27b3ac2d7511..6432123ddff3 100644
--- a/engine/orchestration/src/main/java/com/cloud/agent/manager/AgentManagerImpl.java
+++ b/engine/orchestration/src/main/java/com/cloud/agent/manager/AgentManagerImpl.java
@@ -38,10 +38,6 @@
 import javax.inject.Inject;
 import javax.naming.ConfigurationException;
 
-import com.cloud.configuration.Config;
-import com.cloud.org.Cluster;
-import com.cloud.utils.NumbersUtil;
-import com.cloud.utils.db.GlobalLock;
 import org.apache.cloudstack.agent.lb.IndirectAgentLB;
 import org.apache.cloudstack.ca.CAManager;
 import org.apache.cloudstack.engine.orchestration.service.NetworkOrchestrationService;
@@ -54,6 +50,8 @@
 import org.apache.cloudstack.outofbandmanagement.dao.OutOfBandManagementDao;
 import org.apache.cloudstack.utils.identity.ManagementServerNode;
 import org.apache.commons.lang3.BooleanUtils;
+import org.apache.commons.lang3.StringUtils;
+import org.apache.logging.log4j.ThreadContext;
 
 import com.cloud.agent.AgentManager;
 import com.cloud.agent.Listener;
@@ -80,6 +78,7 @@
 import com.cloud.agent.transport.Request;
 import com.cloud.agent.transport.Response;
 import com.cloud.alert.AlertManager;
+import com.cloud.configuration.Config;
 import com.cloud.configuration.ManagementServiceConfiguration;
 import com.cloud.dc.ClusterVO;
 import com.cloud.dc.DataCenterVO;
@@ -99,15 +98,18 @@
 import com.cloud.host.dao.HostDao;
 import com.cloud.hypervisor.Hypervisor.HypervisorType;
 import com.cloud.hypervisor.HypervisorGuruManager;
+import com.cloud.org.Cluster;
 import com.cloud.resource.Discoverer;
 import com.cloud.resource.ResourceManager;
 import com.cloud.resource.ResourceState;
 import com.cloud.resource.ServerResource;
+import com.cloud.utils.NumbersUtil;
 import com.cloud.utils.Pair;
 import com.cloud.utils.component.ManagerBase;
 import com.cloud.utils.concurrency.NamedThreadFactory;
 import com.cloud.utils.db.DB;
 import com.cloud.utils.db.EntityManager;
+import com.cloud.utils.db.GlobalLock;
 import com.cloud.utils.db.QueryBuilder;
 import com.cloud.utils.db.SearchCriteria.Op;
 import com.cloud.utils.db.TransactionLegacy;
@@ -122,8 +124,6 @@
 import com.cloud.utils.nio.NioServer;
 import com.cloud.utils.nio.Task;
 import com.cloud.utils.time.InaccurateClock;
-import org.apache.commons.lang3.StringUtils;
-import org.apache.logging.log4j.ThreadContext;
 
 /**
  * Implementation of the Agent Manager. This class controls the connection to the agents.
@@ -140,6 +140,7 @@ public class AgentManagerImpl extends ManagerBase implements AgentManager, Handl
     protected List<Pair<Integer, StartupCommandProcessor>> _creationMonitors = new ArrayList<Pair<Integer, StartupCommandProcessor>>(17);
     protected List<Long> _loadingAgents = new ArrayList<Long>();
     private int _monitorId = 0;
+    // FIXME: this is causing contention
     private final Lock _agentStatusLock = new ReentrantLock();
 
     @Inject
@@ -178,7 +179,7 @@ public class AgentManagerImpl extends ManagerBase implements AgentManager, Handl
 
     protected ExecutorService _executor;
     protected ThreadPoolExecutor _connectExecutor;
-    protected ScheduledExecutorService _directAgentExecutor;
+    protected ThreadPoolExecutor _directAgentExecutor;
     protected ScheduledExecutorService _cronJobExecutor;
     protected ScheduledExecutorService _monitorExecutor;
 
@@ -195,6 +196,15 @@ public class AgentManagerImpl extends ManagerBase implements AgentManager, Handl
     protected final ConfigKey<Integer> Workers = new ConfigKey<Integer>("Advanced", Integer.class, "workers", "5",
             "Number of worker threads handling remote agent connections.", false);
     protected final ConfigKey<Integer> Port = new ConfigKey<Integer>("Advanced", Integer.class, "port", "8250", "Port to listen on for remote agent connections.", false);
+    protected final ConfigKey<Integer> RemoteAgentSslHandshakeTimeout = new ConfigKey<>("Advanced",
+            Integer.class, "agent.ssl.handshake.timeout", "30",
+            "Seconds after which SSL handshake times out during remote agent connections.", false);
+    protected final ConfigKey<Integer> RemoteAgentSslHandshakeMinWorkers = new ConfigKey<>("Advanced",
+            Integer.class, "agent.ssl.handshake.min.workers", "5",
+            "Number of minimum worker threads handling SSL handshake with remote agents.", false);
+    protected final ConfigKey<Integer> RemoteAgentSslHandshakeMaxWorkers = new ConfigKey<>("Advanced",
+            Integer.class, "agent.ssl.handshake.max.workers", "50",
+            "Number of maximum worker threads handling SSL handshake with remote agents.", false);
     protected final ConfigKey<Integer> AlertWait = new ConfigKey<Integer>("Advanced", Integer.class, "alert.wait", "1800",
             "Seconds to wait before alerting on a disconnected agent", true);
     protected final ConfigKey<Integer> DirectAgentLoadSize = new ConfigKey<Integer>("Advanced", Integer.class, "direct.agent.load.size", "16",
@@ -211,8 +221,6 @@ public boolean configure(final String name, final Map<String, Object> params) th
 
         logger.info("Ping Timeout is {}.", mgmtServiceConf.getPingTimeout());
 
-        final int threads = DirectAgentLoadSize.value();
-
         _nodeId = ManagementServerNode.getManagementServerId();
         logger.info("Configuring AgentManagerImpl. management server node id(msid): {}.", _nodeId);
 
@@ -223,17 +231,20 @@ public boolean configure(final String name, final Map<String, Object> params) th
 
         registerForHostEvents(new SetHostParamsListener(), true, true, false);
 
-        _executor = new ThreadPoolExecutor(threads, threads, 60l, TimeUnit.SECONDS, new LinkedBlockingQueue<Runnable>(), new NamedThreadFactory("AgentTaskPool"));
+        final int agentTaskThreads = DirectAgentLoadSize.value();
+        _executor = new ThreadPoolExecutor(agentTaskThreads, agentTaskThreads, 60L, TimeUnit.SECONDS, new LinkedBlockingQueue<Runnable>(), new NamedThreadFactory("AgentTaskPool"));
 
         _connectExecutor = new ThreadPoolExecutor(100, 500, 60l, TimeUnit.SECONDS, new LinkedBlockingQueue<Runnable>(), new NamedThreadFactory("AgentConnectTaskPool"));
         // allow core threads to time out even when there are no items in the queue
         _connectExecutor.allowCoreThreadTimeOut(true);
 
-        _connection = new NioServer("AgentManager", Port.value(), Workers.value() + 10, this, caService);
+        _connection = new NioServer("AgentManager", Port.value(), Workers.value() + 10,
+                RemoteAgentSslHandshakeMinWorkers.value(), RemoteAgentSslHandshakeMaxWorkers.value(), this,
+                caService, RemoteAgentSslHandshakeTimeout.value());
         logger.info("Listening on {} with {} workers.", Port.value(), Workers.value());
 
         // executes all agent commands other than cron and ping
-        _directAgentExecutor = new ScheduledThreadPoolExecutor(DirectAgentPoolSize.value(), new NamedThreadFactory("DirectAgent"));
+        _directAgentExecutor = new ThreadPoolExecutor(Math.max(agentTaskThreads/10, 1), DirectAgentPoolSize.value(), 120L, TimeUnit.SECONDS, new LinkedBlockingQueue<>(), new NamedThreadFactory("DirectAgent"));
         // executes cron and ping agent commands
         _cronJobExecutor = new ScheduledThreadPoolExecutor(DirectAgentPoolSize.value(), new NamedThreadFactory("DirectAgentCronJob"));
         logger.debug("Created DirectAgentAttache pool with size: {}.", DirectAgentPoolSize.value());
@@ -1631,7 +1642,7 @@ public void pullAgentOutMaintenance(final long hostId) {
         }
     }
 
-    public ScheduledExecutorService getDirectAgentPool() {
+    public ThreadPoolExecutor getDirectAgentPool() {
         return _directAgentExecutor;
     }
 
@@ -1802,7 +1813,9 @@ public String getConfigComponentName() {
     @Override
     public ConfigKey<?>[] getConfigKeys() {
         return new ConfigKey<?>[] { CheckTxnBeforeSending, Workers, Port, Wait, AlertWait, DirectAgentLoadSize,
-                DirectAgentPoolSize, DirectAgentThreadCap, EnableKVMAutoEnableDisable, ReadyCommandWait };
+                DirectAgentPoolSize, DirectAgentThreadCap, EnableKVMAutoEnableDisable, ReadyCommandWait,
+                RemoteAgentSslHandshakeTimeout, RemoteAgentSslHandshakeMinWorkers, RemoteAgentSslHandshakeMaxWorkers
+        };
     }
 
     protected class SetHostParamsListener implements Listener {
diff --git a/engine/orchestration/src/main/java/com/cloud/agent/manager/ClusteredAgentManagerImpl.java b/engine/orchestration/src/main/java/com/cloud/agent/manager/ClusteredAgentManagerImpl.java
index a7fea0f25331..c8f473ade55f 100644
--- a/engine/orchestration/src/main/java/com/cloud/agent/manager/ClusteredAgentManagerImpl.java
+++ b/engine/orchestration/src/main/java/com/cloud/agent/manager/ClusteredAgentManagerImpl.java
@@ -243,14 +243,14 @@ public Task create(final Task.Type type, final Link link, final byte[] data) {
         return new ClusteredAgentHandler(type, link, data);
     }
 
-    protected AgentAttache createAttache(final long id) {
-        logger.debug("create forwarding ClusteredAgentAttache for {}", id);
-        final HostVO host = _hostDao.findById(id);
-        final AgentAttache attache = new ClusteredAgentAttache(this, id, host.getName());
+
+    protected AgentAttache createAttache(final Host host) {
+            logger.debug("create forwarding ClusteredAgentAttache for {}", host.getId());
+        final AgentAttache attache = new ClusteredAgentAttache(this, host.getId(), host.getName());
         AgentAttache old = null;
         synchronized (_agents) {
-            old = _agents.get(id);
-            _agents.put(id, attache);
+            old = _agents.get(host.getId());
+            _agents.put(host.getId(), attache);
         }
         if (old != null) {
             logger.debug("Remove stale agent attache from current management server");
@@ -546,12 +546,12 @@ protected AgentAttache getAttache(final Long hostId) throws AgentUnavailableExce
         if (agent == null || !agent.forForward()) {
             if (isHostOwnerSwitched(host)) {
                 logger.debug("Host {} has switched to another management server, need to update agent map with a forwarding agent attache",  hostId);
-                agent = createAttache(hostId);
+                agent = createAttache(host);
             }
         }
         if (agent == null) {
             final AgentUnavailableException ex = new AgentUnavailableException("Host with specified id is not in the right state: " + host.getStatus(), hostId);
-            ex.addProxyObject(_entityMgr.findById(Host.class, hostId).getUuid());
+            ex.addProxyObject(host.getUuid());
             throw ex;
         }
 
@@ -1119,7 +1119,7 @@ protected boolean startRebalance(final long hostId) {
             final ClusteredDirectAgentAttache attache = (ClusteredDirectAgentAttache)_agents.get(hostId);
             if (attache != null && attache.getQueueSize() == 0 && attache.getNonRecurringListenersSize() == 0) {
                 handleDisconnectWithoutInvestigation(attache, Event.StartAgentRebalance, true, true);
-                final ClusteredAgentAttache forwardAttache = (ClusteredAgentAttache)createAttache(hostId);
+                final ClusteredAgentAttache forwardAttache = (ClusteredAgentAttache)createAttache(host);
                 if (forwardAttache == null) {
                     logger.warn("Unable to create a forward attache for the host {} as a part of rebalance process", hostId);
                     return false;
diff --git a/engine/orchestration/src/main/java/com/cloud/vm/VirtualMachineManagerImpl.java b/engine/orchestration/src/main/java/com/cloud/vm/VirtualMachineManagerImpl.java
index 7c107ed6f547..590040b31a10 100755
--- a/engine/orchestration/src/main/java/com/cloud/vm/VirtualMachineManagerImpl.java
+++ b/engine/orchestration/src/main/java/com/cloud/vm/VirtualMachineManagerImpl.java
@@ -85,6 +85,7 @@
 import org.apache.cloudstack.storage.datastore.db.PrimaryDataStoreDao;
 import org.apache.cloudstack.storage.datastore.db.StoragePoolVO;
 import org.apache.cloudstack.storage.to.VolumeObjectTO;
+import org.apache.cloudstack.utils.cache.SingleCache;
 import org.apache.cloudstack.utils.identity.ManagementServerNode;
 import org.apache.cloudstack.utils.reflectiontostringbuilderutils.ReflectionToStringBuilderUtils;
 import org.apache.cloudstack.vm.UnmanagedVMsManager;
@@ -406,6 +407,10 @@ public class VirtualMachineManagerImpl extends ManagerBase implements VirtualMac
     private DomainDao domainDao;
     @Inject
     ResourceCleanupService resourceCleanupService;
+    @Inject
+    VmWorkJobDao vmWorkJobDao;
+
+    private SingleCache<List<Long>> vmIdsInProgressCache;
 
     VmWorkJobHandlerProxy _jobHandlerProxy = new VmWorkJobHandlerProxy(this);
 
@@ -450,6 +455,8 @@ public class VirtualMachineManagerImpl extends ManagerBase implements VirtualMac
             Long.class, "systemvm.root.disk.size", "-1",
             "Size of root volume (in GB) of system VMs and virtual routers", true);
 
+    private boolean syncTransitioningVmPowerState;
+
     ScheduledExecutorService _executor = null;
 
     private long _nodeId;
@@ -816,6 +823,7 @@ private void sendModifyTargetsCommand(ModifyTargetsCommand cmd, long hostId) {
 
     @Override
     public boolean start() {
+        vmIdsInProgressCache = new SingleCache<>(10, vmWorkJobDao::listVmIdsWithPendingJob);
         _executor.scheduleAtFixedRate(new CleanupTask(), 5, VmJobStateReportInterval.value(), TimeUnit.SECONDS);
         _executor.scheduleAtFixedRate(new TransitionTask(),  VmOpCleanupInterval.value(), VmOpCleanupInterval.value(), TimeUnit.SECONDS);
         cancelWorkItems(_nodeId);
@@ -843,6 +851,8 @@ public boolean configure(final String name, final Map<String, Object> xmlParams)
 
         _messageBus.subscribe(VirtualMachineManager.Topics.VM_POWER_STATE, MessageDispatcher.getDispatcher(this));
 
+        syncTransitioningVmPowerState = Boolean.TRUE.equals(VmSyncPowerStateTransitioning.value());
+
         return true;
     }
 
@@ -3504,7 +3514,7 @@ public DataCenterDeployment getMigrationDeployment(final VirtualMachine vm, fina
         if (MIGRATE_VM_ACROSS_CLUSTERS.valueIn(host.getDataCenterId()) &&
                 (HypervisorType.VMware.equals(host.getHypervisorType()) || !checkIfVmHasClusterWideVolumes(vm.getId()))) {
             logger.info("Searching for hosts in the zone for vm migration");
-            List<Long> clustersToExclude = _clusterDao.listAllClusters(host.getDataCenterId());
+            List<Long> clustersToExclude = _clusterDao.listAllClusterIds(host.getDataCenterId());
             List<ClusterVO> clusterList = _clusterDao.listByDcHyType(host.getDataCenterId(), host.getHypervisorType().toString());
             for (ClusterVO cluster : clusterList) {
                 clustersToExclude.remove(cluster.getId());
@@ -3793,12 +3803,12 @@ public int getTimeout() {
     public boolean processCommands(final long agentId, final long seq, final Command[] cmds) {
         boolean processed = false;
         for (final Command cmd : cmds) {
+            // FIXME: PingRoutingCommand handler is DB & CPU hotspot
             if (cmd instanceof PingRoutingCommand) {
                 final PingRoutingCommand ping = (PingRoutingCommand)cmd;
                 if (ping.getHostVmStateReport() != null) {
                     _syncMgr.processHostVmStatePingReport(agentId, ping.getHostVmStateReport(), ping.getOutOfBand());
                 }
-
                 scanStalledVMInTransitionStateOnUpHost(agentId);
                 processed = true;
             }
@@ -4756,7 +4766,8 @@ public ConfigKey<?>[] getConfigKeys() {
                 VmOpLockStateRetry, VmOpWaitInterval, ExecuteInSequence, VmJobCheckInterval, VmJobTimeout, VmJobStateReportInterval,
                 VmConfigDriveLabel, VmConfigDriveOnPrimaryPool, VmConfigDriveForceHostCacheUse, VmConfigDriveUseHostCacheOnUnsupportedPool,
                 HaVmRestartHostUp, ResourceCountRunningVMsonly, AllowExposeHypervisorHostname, AllowExposeHypervisorHostnameAccountLevel, SystemVmRootDiskSize,
-                AllowExposeDomainInMetadata, MetadataCustomCloudName, VmMetadataManufacturer, VmMetadataProductName
+                AllowExposeDomainInMetadata, MetadataCustomCloudName, VmMetadataManufacturer, VmMetadataProductName,
+                VmSyncPowerStateTransitioning
         };
     }
 
@@ -4955,19 +4966,36 @@ private void handlePowerOffReportWithNoPendingJobsOnVM(final VMInstanceVO vm) {
     }
 
     private void scanStalledVMInTransitionStateOnUpHost(final long hostId) {
-        final long stallThresholdInMs = VmJobStateReportInterval.value() + (VmJobStateReportInterval.value() >> 1);
-        final Date cutTime = new Date(DateUtil.currentGMTTime().getTime() - stallThresholdInMs);
-        final List<Long> mostlikelyStoppedVMs = listStalledVMInTransitionStateOnUpHost(hostId, cutTime);
-        for (final Long vmId : mostlikelyStoppedVMs) {
-            final VMInstanceVO vm = _vmDao.findById(vmId);
-            assert vm != null;
+        if (!syncTransitioningVmPowerState) {
+            return;
+        }
+        // Check VM that is stuck in Starting, Stopping, Migrating states, we won't check
+        // VMs in expunging state (this need to be handled specially)
+        //
+        // checking condition
+        //      1) no pending VmWork job
+        //      2) on hostId host and host is UP
+        //
+        // When host is UP, sooner or later we will get a report from the host about the VM,
+        // however, if VM is missing from the host report (it may happen in out of band changes
+        // or from behaviour of XS/KVM by design), the VM may not get a chance to run the state-sync logic
+        //
+        // Therefore, we will scan those VMs on UP host based on last update timestamp, if the host is UP
+        // and a VM stalls for status update, we will consider them to be powered off
+        // (which is relatively safe to do so)
+        final long stallThresholdInMs = VmJobStateReportInterval.value() * 2;
+        final long cutTime = new Date(DateUtil.currentGMTTime().getTime() - stallThresholdInMs).getTime();
+        if (!_hostDao.isHostUp(hostId)) {
+            return;
+        }
+        final List<VMInstanceVO> hostTransitionVms = _vmDao.listByHostAndState(hostId, State.Starting, State.Stopping, State.Migrating);
+        final List<VMInstanceVO> mostLikelyStoppedVMs = listStalledVMInTransitionStateOnUpHost(hostTransitionVms, cutTime);
+        for (final VMInstanceVO vm : mostLikelyStoppedVMs) {
             handlePowerOffReportWithNoPendingJobsOnVM(vm);
         }
 
-        final List<Long> vmsWithRecentReport = listVMInTransitionStateWithRecentReportOnUpHost(hostId, cutTime);
-        for (final Long vmId : vmsWithRecentReport) {
-            final VMInstanceVO vm = _vmDao.findById(vmId);
-            assert vm != null;
+        final List<VMInstanceVO> vmsWithRecentReport = listVMInTransitionStateWithRecentReportOnUpHost(hostTransitionVms, cutTime);
+        for (final VMInstanceVO vm : vmsWithRecentReport) {
             if (vm.getPowerState() == PowerState.PowerOn) {
                 handlePowerOnReportWithNoPendingJobsOnVM(vm);
             } else {
@@ -4988,89 +5016,58 @@ private void scanStalledVMInTransitionStateOnDisconnectedHosts() {
         }
     }
 
-    private List<Long> listStalledVMInTransitionStateOnUpHost(final long hostId, final Date cutTime) {
-        final String sql = "SELECT i.* FROM vm_instance as i, host as h WHERE h.status = 'UP' " +
-                "AND h.id = ? AND i.power_state_update_time < ? AND i.host_id = h.id " +
-                "AND (i.state ='Starting' OR i.state='Stopping' OR i.state='Migrating') " +
-                "AND i.id NOT IN (SELECT w.vm_instance_id FROM vm_work_job AS w JOIN async_job AS j ON w.id = j.id WHERE j.job_status = ?)" +
-                "AND i.removed IS NULL";
-
-        final List<Long> l = new ArrayList<>();
-        try (TransactionLegacy txn = TransactionLegacy.open(TransactionLegacy.CLOUD_DB)) {
-            String cutTimeStr = DateUtil.getDateDisplayString(TimeZone.getTimeZone("GMT"), cutTime);
-
-            try {
-                PreparedStatement pstmt = txn.prepareAutoCloseStatement(sql);
-
-                pstmt.setLong(1, hostId);
-                pstmt.setString(2, cutTimeStr);
-                pstmt.setInt(3, JobInfo.Status.IN_PROGRESS.ordinal());
-                final ResultSet rs = pstmt.executeQuery();
-                while (rs.next()) {
-                    l.add(rs.getLong(1));
-                }
-            } catch (SQLException e) {
-                logger.error("Unable to execute SQL [{}] with params {\"h.id\": {}, \"i.power_state_update_time\": \"{}\"} due to [{}].", sql, hostId, cutTimeStr, e.getMessage(), e);
-            }
+    private List<VMInstanceVO> listStalledVMInTransitionStateOnUpHost(
+            final List<VMInstanceVO> transitioningVms, final long cutTime) {
+        if (CollectionUtils.isEmpty(transitioningVms)) {
+            return transitioningVms;
         }
-        return l;
+        List<Long> vmIdsInProgress = vmIdsInProgressCache.get();
+        return transitioningVms.stream()
+                .filter(v -> v.getPowerStateUpdateTime().getTime() < cutTime && !vmIdsInProgress.contains(v.getId()))
+                .collect(Collectors.toList());
     }
 
-    private List<Long> listVMInTransitionStateWithRecentReportOnUpHost(final long hostId, final Date cutTime) {
-        final String sql = "SELECT i.* FROM vm_instance as i, host as h WHERE h.status = 'UP' " +
-                "AND h.id = ? AND i.power_state_update_time > ? AND i.host_id = h.id " +
-                "AND (i.state ='Starting' OR i.state='Stopping' OR i.state='Migrating') " +
-                "AND i.id NOT IN (SELECT w.vm_instance_id FROM vm_work_job AS w JOIN async_job AS j ON w.id = j.id WHERE j.job_status = ?)" +
-                "AND i.removed IS NULL";
-
-        final List<Long> l = new ArrayList<>();
-        try (TransactionLegacy txn = TransactionLegacy.open(TransactionLegacy.CLOUD_DB)) {
-            String cutTimeStr = DateUtil.getDateDisplayString(TimeZone.getTimeZone("GMT"), cutTime);
-            int jobStatusInProgress = JobInfo.Status.IN_PROGRESS.ordinal();
-
-            try {
-                PreparedStatement pstmt = txn.prepareAutoCloseStatement(sql);
-
-                pstmt.setLong(1, hostId);
-                pstmt.setString(2, cutTimeStr);
-                pstmt.setInt(3, jobStatusInProgress);
-                final ResultSet rs = pstmt.executeQuery();
-                while (rs.next()) {
-                    l.add(rs.getLong(1));
-                }
-            } catch (final SQLException e) {
-                logger.error("Unable to execute SQL [{}] with params {\"h.id\": {}, \"i.power_state_update_time\": \"{}\", \"j.job_status\": {}} due to [{}].", sql, hostId, cutTimeStr, jobStatusInProgress, e.getMessage(), e);
-            }
-            return l;
+    private List<VMInstanceVO> listVMInTransitionStateWithRecentReportOnUpHost(
+            final List<VMInstanceVO> transitioningVms, final long cutTime) {
+        if (CollectionUtils.isEmpty(transitioningVms)) {
+            return transitioningVms;
         }
+        List<Long> vmIdsInProgress = vmIdsInProgressCache.get();
+        return transitioningVms.stream()
+                .filter(v -> v.getPowerStateUpdateTime().getTime() > cutTime && !vmIdsInProgress.contains(v.getId()))
+                .collect(Collectors.toList());
     }
 
     private List<Long> listStalledVMInTransitionStateOnDisconnectedHosts(final Date cutTime) {
-        final String sql = "SELECT i.* FROM vm_instance as i, host as h WHERE h.status != 'UP' " +
-                "AND i.power_state_update_time < ? AND i.host_id = h.id " +
-                "AND (i.state ='Starting' OR i.state='Stopping' OR i.state='Migrating') " +
-                "AND i.id NOT IN (SELECT w.vm_instance_id FROM vm_work_job AS w JOIN async_job AS j ON w.id = j.id WHERE j.job_status = ?)" +
-                "AND i.removed IS NULL";
+        final String sql = "SELECT i.*\n" +
+                "FROM vm_instance AS i\n" +
+                "INNER JOIN host AS h ON i.host_id = h.id\n" +
+                "WHERE h.status != 'UP' \n" +
+                "  AND i.power_state_update_time < ?\n" +
+                "  AND i.state IN ('Starting', 'Stopping', 'Migrating')\n" +
+                "  AND i.id NOT IN (SELECT vm_instance_id FROM vm_work_job AS w\n" +
+                "                    INNER JOIN async_job AS j ON w.id = j.id\n" +
+                "                    WHERE j.job_status = ?)\n" +
+                "  AND i.removed IS NULL";
 
         final List<Long> l = new ArrayList<>();
-        try (TransactionLegacy txn = TransactionLegacy.open(TransactionLegacy.CLOUD_DB)) {
-            String cutTimeStr = DateUtil.getDateDisplayString(TimeZone.getTimeZone("GMT"), cutTime);
-            int jobStatusInProgress = JobInfo.Status.IN_PROGRESS.ordinal();
+        TransactionLegacy txn = TransactionLegacy.currentTxn();
+        String cutTimeStr = DateUtil.getDateDisplayString(TimeZone.getTimeZone("GMT"), cutTime);
+        int jobStatusInProgress = JobInfo.Status.IN_PROGRESS.ordinal();
 
-            try {
-                PreparedStatement pstmt = txn.prepareAutoCloseStatement(sql);
+        try {
+            PreparedStatement pstmt = txn.prepareAutoCloseStatement(sql);
 
-                pstmt.setString(1, cutTimeStr);
-                pstmt.setInt(2, jobStatusInProgress);
-                final ResultSet rs = pstmt.executeQuery();
-                while (rs.next()) {
-                    l.add(rs.getLong(1));
-                }
-            } catch (final SQLException e) {
-                logger.error("Unable to execute SQL [{}] with params {\"i.power_state_update_time\": \"{}\", \"j.job_status\": {}} due to [{}].", sql, cutTimeStr, jobStatusInProgress, e.getMessage(), e);
+            pstmt.setString(1, cutTimeStr);
+            pstmt.setInt(2, jobStatusInProgress);
+            final ResultSet rs = pstmt.executeQuery();
+            while (rs.next()) {
+                l.add(rs.getLong(1));
             }
-            return l;
+        } catch (final SQLException e) {
+            logger.error("Unable to execute SQL [{}] with params {\"i.power_state_update_time\": \"{}\", \"j.job_status\": {}} due to [{}].", sql, cutTimeStr, jobStatusInProgress, e.getMessage(), e);
         }
+        return l;
     }
 
     public class VmStateSyncOutcome extends OutcomeImpl<VirtualMachine> {
@@ -5950,29 +5947,23 @@ protected VMInstanceVO findVmById(Long vmId) {
     }
 
     @Override
-    public HashMap<Long, ? extends VmStats> getVirtualMachineStatistics(long hostId, String hostName, List<Long> vmIds) {
+    public HashMap<Long, ? extends VmStats> getVirtualMachineStatistics(Host host, List<Long> vmIds) {
         HashMap<Long, VmStatsEntry> vmStatsById = new HashMap<>();
         if (CollectionUtils.isEmpty(vmIds)) {
             return vmStatsById;
         }
-        Map<Long, VMInstanceVO> vmMap = new HashMap<>();
-        for (Long vmId : vmIds) {
-            vmMap.put(vmId, _vmDao.findById(vmId));
-        }
-        return getVirtualMachineStatistics(hostId, hostName, vmMap);
+        Map<String, Long> vmMap = _vmDao.getNameIdMapForVmIds(vmIds);
+        return getVirtualMachineStatistics(host, vmMap);
     }
 
     @Override
-    public HashMap<Long, ? extends VmStats> getVirtualMachineStatistics(long hostId, String hostName, Map<Long, ? extends VirtualMachine> vmMap) {
+    public HashMap<Long, ? extends VmStats> getVirtualMachineStatistics(Host host, Map<String, Long> vmInstanceNameIdMap) {
         HashMap<Long, VmStatsEntry> vmStatsById = new HashMap<>();
-        if (MapUtils.isEmpty(vmMap)) {
+        if (MapUtils.isEmpty(vmInstanceNameIdMap)) {
             return vmStatsById;
         }
-        Map<String, Long> vmNames = new HashMap<>();
-        for (Map.Entry<Long, ? extends VirtualMachine> vmEntry : vmMap.entrySet()) {
-            vmNames.put(vmEntry.getValue().getInstanceName(), vmEntry.getKey());
-        }
-        Answer answer = _agentMgr.easySend(hostId, new GetVmStatsCommand(new ArrayList<>(vmNames.keySet()), _hostDao.findById(hostId).getGuid(), hostName));
+        Answer answer = _agentMgr.easySend(host.getId(), new GetVmStatsCommand(
+                new ArrayList<>(vmInstanceNameIdMap.keySet()), host.getGuid(), host.getName()));
         if (answer == null || !answer.getResult()) {
             logger.warn("Unable to obtain VM statistics.");
             return vmStatsById;
@@ -5983,23 +5974,20 @@ protected VMInstanceVO findVmById(Long vmId) {
                 return vmStatsById;
             }
             for (Map.Entry<String, VmStatsEntry> entry : vmStatsByName.entrySet()) {
-                vmStatsById.put(vmNames.get(entry.getKey()), entry.getValue());
+                vmStatsById.put(vmInstanceNameIdMap.get(entry.getKey()), entry.getValue());
             }
         }
         return vmStatsById;
     }
 
     @Override
-    public HashMap<Long, List<? extends VmDiskStats>> getVmDiskStatistics(long hostId, String hostName, Map<Long, ? extends VirtualMachine> vmMap) {
+    public HashMap<Long, List<? extends VmDiskStats>> getVmDiskStatistics(Host host, Map<String, Long> vmInstanceNameIdMap) {
         HashMap<Long, List<? extends  VmDiskStats>> vmDiskStatsById = new HashMap<>();
-        if (MapUtils.isEmpty(vmMap)) {
+        if (MapUtils.isEmpty(vmInstanceNameIdMap)) {
             return vmDiskStatsById;
         }
-        Map<String, Long> vmNames = new HashMap<>();
-        for (Map.Entry<Long, ? extends VirtualMachine> vmEntry : vmMap.entrySet()) {
-            vmNames.put(vmEntry.getValue().getInstanceName(), vmEntry.getKey());
-        }
-        Answer answer = _agentMgr.easySend(hostId, new GetVmDiskStatsCommand(new ArrayList<>(vmNames.keySet()), _hostDao.findById(hostId).getGuid(), hostName));
+        Answer answer = _agentMgr.easySend(host.getId(), new GetVmDiskStatsCommand(
+                new ArrayList<>(vmInstanceNameIdMap.keySet()), host.getGuid(), host.getName()));
         if (answer == null || !answer.getResult()) {
             logger.warn("Unable to obtain VM disk statistics.");
             return vmDiskStatsById;
@@ -6010,23 +5998,20 @@ public HashMap<Long, List<? extends VmDiskStats>> getVmDiskStatistics(long hostI
                 return vmDiskStatsById;
             }
             for (Map.Entry<String, List<VmDiskStatsEntry>> entry: vmDiskStatsByName.entrySet()) {
-                vmDiskStatsById.put(vmNames.get(entry.getKey()), entry.getValue());
+                vmDiskStatsById.put(vmInstanceNameIdMap.get(entry.getKey()), entry.getValue());
             }
         }
         return vmDiskStatsById;
     }
 
     @Override
-    public HashMap<Long, List<? extends VmNetworkStats>> getVmNetworkStatistics(long hostId, String hostName, Map<Long, ? extends VirtualMachine> vmMap) {
+    public HashMap<Long, List<? extends VmNetworkStats>> getVmNetworkStatistics(Host host, Map<String, Long> vmInstanceNameIdMap) {
         HashMap<Long, List<? extends VmNetworkStats>> vmNetworkStatsById = new HashMap<>();
-        if (MapUtils.isEmpty(vmMap)) {
+        if (MapUtils.isEmpty(vmInstanceNameIdMap)) {
             return vmNetworkStatsById;
         }
-        Map<String, Long> vmNames = new HashMap<>();
-        for (Map.Entry<Long, ? extends VirtualMachine> vmEntry : vmMap.entrySet()) {
-            vmNames.put(vmEntry.getValue().getInstanceName(), vmEntry.getKey());
-        }
-        Answer answer = _agentMgr.easySend(hostId, new GetVmNetworkStatsCommand(new ArrayList<>(vmNames.keySet()), _hostDao.findById(hostId).getGuid(), hostName));
+        Answer answer = _agentMgr.easySend(host.getId(), new GetVmNetworkStatsCommand(
+                new ArrayList<>(vmInstanceNameIdMap.keySet()), host.getGuid(), host.getName()));
         if (answer == null || !answer.getResult()) {
             logger.warn("Unable to obtain VM network statistics.");
             return vmNetworkStatsById;
@@ -6037,7 +6022,7 @@ public HashMap<Long, List<? extends VmNetworkStats>> getVmNetworkStatistics(long
                 return vmNetworkStatsById;
             }
             for (Map.Entry<String, List<VmNetworkStatsEntry>> entry: vmNetworkStatsByName.entrySet()) {
-                vmNetworkStatsById.put(vmNames.get(entry.getKey()), entry.getValue());
+                vmNetworkStatsById.put(vmInstanceNameIdMap.get(entry.getKey()), entry.getValue());
             }
         }
         return vmNetworkStatsById;
diff --git a/engine/orchestration/src/main/java/com/cloud/vm/VirtualMachinePowerStateSyncImpl.java b/engine/orchestration/src/main/java/com/cloud/vm/VirtualMachinePowerStateSyncImpl.java
index 4c89a75d2151..4b7fd8cc8327 100644
--- a/engine/orchestration/src/main/java/com/cloud/vm/VirtualMachinePowerStateSyncImpl.java
+++ b/engine/orchestration/src/main/java/com/cloud/vm/VirtualMachinePowerStateSyncImpl.java
@@ -16,23 +16,24 @@
 // under the License.
 package com.cloud.vm;
 
-import java.text.SimpleDateFormat;
 import java.util.Date;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.Set;
+import java.util.stream.Collectors;
 
 import javax.inject.Inject;
 
 import org.apache.cloudstack.framework.messagebus.MessageBus;
 import org.apache.cloudstack.framework.messagebus.PublishScope;
-import org.apache.logging.log4j.Logger;
+import org.apache.commons.collections.MapUtils;
 import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
 
 import com.cloud.agent.api.HostVmStateReportEntry;
 import com.cloud.configuration.ManagementServiceConfiguration;
 import com.cloud.utils.DateUtil;
-import com.cloud.utils.exception.CloudRuntimeException;
 import com.cloud.vm.dao.VMInstanceDao;
 
 public class VirtualMachinePowerStateSyncImpl implements VirtualMachinePowerStateSync {
@@ -67,119 +68,121 @@ public void processHostVmStatePingReport(long hostId, Map<String, HostVmStateRep
         processReport(hostId, translatedInfo, force);
     }
 
-    private void processReport(long hostId, Map<Long, VirtualMachine.PowerState> translatedInfo, boolean force) {
-
-        logger.debug("Process VM state report. host: {}, number of records in report: {}.", hostId, translatedInfo.size());
-
-        for (Map.Entry<Long, VirtualMachine.PowerState> entry : translatedInfo.entrySet()) {
-
-            logger.debug("VM state report. host: {}, vm id: {}, power state: {}.", hostId, entry.getKey(), entry.getValue());
-
-            if (_instanceDao.updatePowerState(entry.getKey(), hostId, entry.getValue(), DateUtil.currentGMTTime())) {
-                logger.debug("VM state report is updated. host: {}, vm id: {}, power state: {}.", hostId, entry.getKey(), entry.getValue());
-
-                _messageBus.publish(null, VirtualMachineManager.Topics.VM_POWER_STATE, PublishScope.GLOBAL, entry.getKey());
-            } else {
-                logger.trace("VM power state does not change, skip DB writing. vm id: {}.", entry.getKey());
+    private void updateAndPublishVmPowerStates(long hostId, Map<Long, VirtualMachine.PowerState> instancePowerStates,
+           Date updateTime) {
+        if (instancePowerStates.isEmpty()) {
+            return;
+        }
+        Set<Long> vmIds = instancePowerStates.keySet();
+        Map<Long, VirtualMachine.PowerState> notUpdated = _instanceDao.updatePowerState(instancePowerStates, hostId,
+                updateTime);
+        if (notUpdated.size() <= vmIds.size()) {
+            for (Long vmId : vmIds) {
+                if (!notUpdated.isEmpty() && !notUpdated.containsKey(vmId)) {
+                    logger.debug("VM state report is updated. host: {}, vm id: {}}, power state: {}}",
+                            hostId, vmId, instancePowerStates.get(vmId));
+                    _messageBus.publish(null, VirtualMachineManager.Topics.VM_POWER_STATE,
+                            PublishScope.GLOBAL, vmId);
+                    continue;
+                }
+                logger.trace("VM power state does not change, skip DB writing. vm id: {}", vmId);
             }
         }
+    }
 
+    private void processMissingVmReport(long hostId, Set<Long> vmIds, boolean force) {
         // any state outdates should be checked against the time before this list was retrieved
         Date startTime = DateUtil.currentGMTTime();
         // for all running/stopping VMs, we provide monitoring of missing report
-        List<VMInstanceVO> vmsThatAreMissingReport = _instanceDao.findByHostInStates(hostId, VirtualMachine.State.Running,
-                VirtualMachine.State.Stopping, VirtualMachine.State.Starting);
-        java.util.Iterator<VMInstanceVO> it = vmsThatAreMissingReport.iterator();
-        while (it.hasNext()) {
-            VMInstanceVO instance = it.next();
-            if (translatedInfo.get(instance.getId()) != null)
-                it.remove();
-        }
-
+        List<VMInstanceVO> vmsThatAreMissingReport = _instanceDao.findByHostInStatesExcluding(hostId, vmIds,
+                VirtualMachine.State.Running, VirtualMachine.State.Stopping, VirtualMachine.State.Starting);
         // here we need to be wary of out of band migration as opposed to other, more unexpected state changes
-        if (vmsThatAreMissingReport.size() > 0) {
-            Date currentTime = DateUtil.currentGMTTime();
-            logger.debug("Run missing VM report. current time: {}", currentTime.getTime());
-
-            // 2 times of sync-update interval for graceful period
-            long milliSecondsGracefullPeriod = mgmtServiceConf.getPingInterval() * 2000L;
-
-            for (VMInstanceVO instance : vmsThatAreMissingReport) {
-
-                // Make sure powerState is up to date for missing VMs
-                try {
-                    if (!force && !_instanceDao.isPowerStateUpToDate(instance.getId())) {
-                        logger.warn("Detected missing VM but power state is outdated, wait for another process report run for VM id: {}.", instance.getId());
-                        _instanceDao.resetVmPowerStateTracking(instance.getId());
-                        continue;
-                    }
-                } catch (CloudRuntimeException e) {
-                    logger.warn("Checked for missing powerstate of a none existing vm", e);
-                    continue;
-                }
+        if (vmsThatAreMissingReport.isEmpty()) {
+            return;
+        }
+        Date currentTime = DateUtil.currentGMTTime();
+        if (logger.isDebugEnabled()) {
+            logger.debug("Run missing VM report. current time: " + currentTime.getTime());
+        }
+        if (!force) {
+            List<Long> outdatedVms = vmsThatAreMissingReport.stream()
+                    .filter(v -> !_instanceDao.isPowerStateUpToDate(v))
+                    .map(VMInstanceVO::getId)
+                    .collect(Collectors.toList());
+            _instanceDao.resetVmPowerStateTracking(outdatedVms);
+            vmsThatAreMissingReport = vmsThatAreMissingReport.stream()
+                    .filter(v -> !outdatedVms.contains(v.getId()))
+                    .collect(Collectors.toList());
+        }
 
-                Date vmStateUpdateTime = instance.getPowerStateUpdateTime();
+        // 2 times of sync-update interval for graceful period
+        long milliSecondsGracefulPeriod = mgmtServiceConf.getPingInterval() * 2000L;
+        Map<Long, VirtualMachine.PowerState> instancePowerStates = new HashMap<>();
+        for (VMInstanceVO instance : vmsThatAreMissingReport) {
+            Date vmStateUpdateTime = instance.getPowerStateUpdateTime();
+            if (vmStateUpdateTime == null) {
+                logger.warn("VM power state update time is null, falling back to update time for vm id: " + instance.getId());
+                vmStateUpdateTime = instance.getUpdateTime();
                 if (vmStateUpdateTime == null) {
-                    logger.warn("VM power state update time is null, falling back to update time for vm id: {}.", instance.getId());
-                    vmStateUpdateTime = instance.getUpdateTime();
-                    if (vmStateUpdateTime == null) {
-                        logger.warn("VM update time is null, falling back to creation time for vm id: {}", instance.getId());
-                        vmStateUpdateTime = instance.getCreated();
-                    }
+                    logger.warn("VM update time is null, falling back to creation time for vm id: " + instance.getId());
+                    vmStateUpdateTime = instance.getCreated();
                 }
-
-                String lastTime = new SimpleDateFormat("yyyy/MM/dd'T'HH:mm:ss.SSS'Z'").format(vmStateUpdateTime);
-                logger.debug("Detected missing VM. host: {}, vm id: {}({}), power state: {}, last state update: {}"
+            }
+            if (logger.isDebugEnabled()) {
+                logger.debug(
+                        String.format("Detected missing VM. host: %d, vm id: %d(%s), power state: %s, last state update: %s"
                                 , hostId
                                 , instance.getId()
                                 , instance.getUuid()
                                 , VirtualMachine.PowerState.PowerReportMissing
-                                , lastTime);
-
-                long milliSecondsSinceLastStateUpdate = currentTime.getTime() - vmStateUpdateTime.getTime();
-
-                if (force || milliSecondsSinceLastStateUpdate > milliSecondsGracefullPeriod) {
-                    logger.debug("vm id: {} - time since last state update({}ms) has passed graceful period.", instance.getId(), milliSecondsSinceLastStateUpdate);
-
-                    // this is were a race condition might have happened if we don't re-fetch the instance;
-                    // between the startime of this job and the currentTime of this missing-branch
-                    // an update might have occurred that we should not override in case of out of band migration
-                    if (_instanceDao.updatePowerState(instance.getId(), hostId, VirtualMachine.PowerState.PowerReportMissing, startTime)) {
-                        logger.debug("VM state report is updated. host: {}, vm id: {}, power state: PowerReportMissing.", hostId, instance.getId());
-
-                        _messageBus.publish(null, VirtualMachineManager.Topics.VM_POWER_STATE, PublishScope.GLOBAL, instance.getId());
-                    } else {
-                        logger.debug("VM power state does not change, skip DB writing. vm id: {}", instance.getId());
-                    }
-                } else {
-                    logger.debug("vm id: {} - time since last state update({}ms) has not passed graceful period yet.", instance.getId(), milliSecondsSinceLastStateUpdate);
-                }
+                                , DateUtil.getOutputString(vmStateUpdateTime)));
+            }
+            long milliSecondsSinceLastStateUpdate = currentTime.getTime() - vmStateUpdateTime.getTime();
+            if (force || (milliSecondsSinceLastStateUpdate > milliSecondsGracefulPeriod)) {
+                logger.debug("vm id: {} - time since last state update({} ms) has passed graceful period",
+                        instance.getId(), milliSecondsSinceLastStateUpdate);
+                // this is where a race condition might have happened if we don't re-fetch the instance;
+                // between the startime of this job and the currentTime of this missing-branch
+                // an update might have occurred that we should not override in case of out of band migration
+                instancePowerStates.put(instance.getId(), VirtualMachine.PowerState.PowerReportMissing);
+            } else {
+                logger.debug("vm id: {} - time since last state update({} ms) has not passed graceful period yet",
+                        instance.getId(), milliSecondsSinceLastStateUpdate);
             }
         }
+        updateAndPublishVmPowerStates(hostId, instancePowerStates, startTime);
+    }
+
+    private void processReport(long hostId, Map<Long, VirtualMachine.PowerState> translatedInfo, boolean force) {
+        if (logger.isDebugEnabled()) {
+            logger.debug("Process VM state report. Host: {}, number of records in report: {}. VMs: [{}]",
+                    hostId,
+                    translatedInfo.size(),
+                    translatedInfo.entrySet().stream().map(entry -> entry.getKey() + ":" + entry.getValue())
+                            .collect(Collectors.joining(", ")) + "]");
+        }
+        updateAndPublishVmPowerStates(hostId, translatedInfo, DateUtil.currentGMTTime());
+
+        processMissingVmReport(hostId, translatedInfo.keySet(), force);
 
         logger.debug("Done with process of VM state report. host: {}", hostId);
     }
 
     @Override
     public Map<Long, VirtualMachine.PowerState> convertVmStateReport(Map<String, HostVmStateReportEntry> states) {
-        final HashMap<Long, VirtualMachine.PowerState> map = new HashMap<Long, VirtualMachine.PowerState>();
-        if (states == null) {
+        final HashMap<Long, VirtualMachine.PowerState> map = new HashMap<>();
+        if (MapUtils.isEmpty(states)) {
             return map;
         }
-
+        Map<String, Long> nameIdMap = _instanceDao.getNameIdMapForVmInstanceNames(states.keySet());
         for (Map.Entry<String, HostVmStateReportEntry> entry : states.entrySet()) {
-            VMInstanceVO vm = findVM(entry.getKey());
-            if (vm != null) {
-                map.put(vm.getId(), entry.getValue().getState());
+            Long id = nameIdMap.get(entry.getKey());
+            if (id != null) {
+                map.put(id, entry.getValue().getState());
             } else {
                 logger.debug("Unable to find matched VM in CloudStack DB. name: {}", entry.getKey());
             }
         }
-
         return map;
     }
-
-    private VMInstanceVO findVM(String vmName) {
-        return _instanceDao.findVMByInstanceName(vmName);
-    }
 }
diff --git a/engine/schema/src/main/java/com/cloud/capacity/dao/CapacityDao.java b/engine/schema/src/main/java/com/cloud/capacity/dao/CapacityDao.java
index 9616f31d0c5c..1bb79ce417aa 100644
--- a/engine/schema/src/main/java/com/cloud/capacity/dao/CapacityDao.java
+++ b/engine/schema/src/main/java/com/cloud/capacity/dao/CapacityDao.java
@@ -28,6 +28,8 @@
 public interface CapacityDao extends GenericDao<CapacityVO, Long> {
     CapacityVO findByHostIdType(Long hostId, short capacityType);
 
+    List<CapacityVO> listByHostIdTypes(Long hostId, List<Short> capacityTypes);
+
     List<Long> listClustersInZoneOrPodByHostCapacities(long id, long vmId, int requiredCpu, long requiredRam, short capacityTypeForOrdering, boolean isZone);
 
     List<Long> listHostsWithEnoughCapacity(int requiredCpu, long requiredRam, Long clusterId, String hostType);
diff --git a/engine/schema/src/main/java/com/cloud/capacity/dao/CapacityDaoImpl.java b/engine/schema/src/main/java/com/cloud/capacity/dao/CapacityDaoImpl.java
index 3acae985af4b..5e7eee4566c1 100644
--- a/engine/schema/src/main/java/com/cloud/capacity/dao/CapacityDaoImpl.java
+++ b/engine/schema/src/main/java/com/cloud/capacity/dao/CapacityDaoImpl.java
@@ -671,6 +671,18 @@ public CapacityVO findByHostIdType(Long hostId, short capacityType) {
         return findOneBy(sc);
     }
 
+    @Override
+    public List<CapacityVO> listByHostIdTypes(Long hostId, List<Short> capacityTypes) {
+        SearchBuilder<CapacityVO> sb = createSearchBuilder();
+        sb.and("hostId", sb.entity().getHostOrPoolId(), SearchCriteria.Op.EQ);
+        sb.and("type", sb.entity().getCapacityType(), SearchCriteria.Op.IN);
+        sb.done();
+        SearchCriteria<CapacityVO> sc = sb.create();
+        sc.setParameters("hostId", hostId);
+        sc.setParameters("type", capacityTypes.toArray());
+        return listBy(sc);
+    }
+
     @Override
     public List<Long> listClustersInZoneOrPodByHostCapacities(long id, long vmId, int requiredCpu, long requiredRam, short capacityTypeForOrdering, boolean isZone) {
         TransactionLegacy txn = TransactionLegacy.currentTxn();
diff --git a/engine/schema/src/main/java/com/cloud/dc/ClusterDetailsDao.java b/engine/schema/src/main/java/com/cloud/dc/ClusterDetailsDao.java
index 06c9c5255048..5daab544b216 100644
--- a/engine/schema/src/main/java/com/cloud/dc/ClusterDetailsDao.java
+++ b/engine/schema/src/main/java/com/cloud/dc/ClusterDetailsDao.java
@@ -16,6 +16,7 @@
 // under the License.
 package com.cloud.dc;
 
+import java.util.Collection;
 import java.util.Map;
 
 import com.cloud.utils.db.GenericDao;
@@ -29,6 +30,8 @@ public interface ClusterDetailsDao extends GenericDao<ClusterDetailsVO, Long> {
 
     ClusterDetailsVO findDetail(long clusterId, String name);
 
+    Map<String, String> findDetails(long clusterId, Collection<String> names);
+
     void deleteDetails(long clusterId);
 
     String getVmwareDcName(Long clusterId);
diff --git a/engine/schema/src/main/java/com/cloud/dc/ClusterDetailsDaoImpl.java b/engine/schema/src/main/java/com/cloud/dc/ClusterDetailsDaoImpl.java
index 0e40f8475c16..a4f6acb90576 100644
--- a/engine/schema/src/main/java/com/cloud/dc/ClusterDetailsDaoImpl.java
+++ b/engine/schema/src/main/java/com/cloud/dc/ClusterDetailsDaoImpl.java
@@ -16,13 +16,16 @@
 // under the License.
 package com.cloud.dc;
 
+import java.util.Collection;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.stream.Collectors;
 
 import org.apache.cloudstack.framework.config.ConfigKey;
 import org.apache.cloudstack.framework.config.ConfigKey.Scope;
 import org.apache.cloudstack.framework.config.ScopedConfigStorage;
+import org.apache.commons.collections.CollectionUtils;
 
 import com.cloud.utils.crypt.DBEncryptionUtil;
 import com.cloud.utils.db.GenericDaoBase;
@@ -82,6 +85,23 @@ public Map<String, String> findDetails(long clusterId) {
         return details;
     }
 
+    @Override
+    public Map<String, String> findDetails(long clusterId, Collection<String> names) {
+        if (CollectionUtils.isEmpty(names)) {
+            return new HashMap<>();
+        }
+        SearchBuilder<ClusterDetailsVO> sb = createSearchBuilder();
+        sb.and("clusterId", sb.entity().getClusterId(), SearchCriteria.Op.EQ);
+        sb.and("name", sb.entity().getName(), SearchCriteria.Op.IN);
+        sb.done();
+        SearchCriteria<ClusterDetailsVO> sc = sb.create();
+        sc.setParameters("clusterId", clusterId);
+        sc.setParameters("name", names.toArray());
+        List<ClusterDetailsVO> results = search(sc, null);
+        return results.stream()
+                .collect(Collectors.toMap(ClusterDetailsVO::getName, ClusterDetailsVO::getValue));
+    }
+
     @Override
     public void deleteDetails(long clusterId) {
         SearchCriteria<ClusterDetailsVO> sc = ClusterSearch.create();
diff --git a/engine/schema/src/main/java/com/cloud/dc/dao/ClusterDao.java b/engine/schema/src/main/java/com/cloud/dc/dao/ClusterDao.java
index 6ecfdaeb0584..577c9cf1026c 100644
--- a/engine/schema/src/main/java/com/cloud/dc/dao/ClusterDao.java
+++ b/engine/schema/src/main/java/com/cloud/dc/dao/ClusterDao.java
@@ -16,15 +16,15 @@
 // under the License.
 package com.cloud.dc.dao;
 
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+
 import com.cloud.cpu.CPU;
 import com.cloud.dc.ClusterVO;
 import com.cloud.hypervisor.Hypervisor.HypervisorType;
 import com.cloud.utils.db.GenericDao;
 
-import java.util.List;
-import java.util.Map;
-import java.util.Set;
-
 public interface ClusterDao extends GenericDao<ClusterVO, Long> {
     List<ClusterVO> listByPodId(long podId);
 
@@ -36,7 +36,7 @@ public interface ClusterDao extends GenericDao<ClusterVO, Long> {
 
     List<HypervisorType> getAvailableHypervisorInZone(Long zoneId);
 
-    Set<HypervisorType> getDistictAvailableHypervisorsAcrossClusters();
+    Set<HypervisorType> getDistinctAvailableHypervisorsAcrossClusters();
 
     List<ClusterVO> listByDcHyType(long dcId, String hyType);
 
@@ -46,13 +46,19 @@ public interface ClusterDao extends GenericDao<ClusterVO, Long> {
 
     List<Long> listClustersWithDisabledPods(long zoneId);
 
+    Integer countAllByDcId(long zoneId);
+
+    Integer countAllManagedAndEnabledByDcId(long zoneId);
+
     List<ClusterVO> listClustersByDcId(long zoneId);
 
-    List<Long> listAllClusters(Long zoneId);
+    List<Long> listAllClusterIds(Long zoneId);
 
     boolean getSupportsResigning(long clusterId);
 
     List<CPU.CPUArch> getClustersArchsByZone(long zoneId);
 
     List<ClusterVO> listClustersByArchAndZoneId(long zoneId, CPU.CPUArch arch);
+
+    List<Long> listAllIds();
 }
diff --git a/engine/schema/src/main/java/com/cloud/dc/dao/ClusterDaoImpl.java b/engine/schema/src/main/java/com/cloud/dc/dao/ClusterDaoImpl.java
index 9a56f0f2d949..4c2c4e9db336 100644
--- a/engine/schema/src/main/java/com/cloud/dc/dao/ClusterDaoImpl.java
+++ b/engine/schema/src/main/java/com/cloud/dc/dao/ClusterDaoImpl.java
@@ -16,6 +16,21 @@
 // under the License.
 package com.cloud.dc.dao;
 
+import java.sql.PreparedStatement;
+import java.sql.ResultSet;
+import java.sql.SQLException;
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+import java.util.stream.Collectors;
+
+import javax.inject.Inject;
+
+import org.springframework.stereotype.Component;
+
 import com.cloud.cpu.CPU;
 import com.cloud.dc.ClusterDetailsDao;
 import com.cloud.dc.ClusterDetailsVO;
@@ -23,6 +38,7 @@
 import com.cloud.dc.HostPodVO;
 import com.cloud.hypervisor.Hypervisor.HypervisorType;
 import com.cloud.org.Grouping;
+import com.cloud.org.Managed;
 import com.cloud.utils.db.GenericDaoBase;
 import com.cloud.utils.db.GenericSearchBuilder;
 import com.cloud.utils.db.JoinBuilder;
@@ -32,19 +48,6 @@
 import com.cloud.utils.db.SearchCriteria.Op;
 import com.cloud.utils.db.TransactionLegacy;
 import com.cloud.utils.exception.CloudRuntimeException;
-import org.springframework.stereotype.Component;
-
-import javax.inject.Inject;
-import java.sql.PreparedStatement;
-import java.sql.ResultSet;
-import java.sql.SQLException;
-import java.util.ArrayList;
-import java.util.HashMap;
-import java.util.HashSet;
-import java.util.List;
-import java.util.Map;
-import java.util.Set;
-import java.util.stream.Collectors;
 
 @Component
 public class ClusterDaoImpl extends GenericDaoBase<ClusterVO, Long> implements ClusterDao {
@@ -58,7 +61,6 @@ public class ClusterDaoImpl extends GenericDaoBase<ClusterVO, Long> implements C
     protected final SearchBuilder<ClusterVO> ClusterSearch;
     protected final SearchBuilder<ClusterVO> ClusterDistinctArchSearch;
     protected final SearchBuilder<ClusterVO> ClusterArchSearch;
-
     protected GenericSearchBuilder<ClusterVO, Long> ClusterIdSearch;
 
     private static final String GET_POD_CLUSTER_MAP_PREFIX = "SELECT pod_id, id FROM cloud.cluster WHERE cluster.id IN( ";
@@ -98,6 +100,8 @@ public ClusterDaoImpl() {
 
         ZoneClusterSearch = createSearchBuilder();
         ZoneClusterSearch.and("dataCenterId", ZoneClusterSearch.entity().getDataCenterId(), SearchCriteria.Op.EQ);
+        ZoneClusterSearch.and("allocationState", ZoneClusterSearch.entity().getAllocationState(), Op.EQ);
+        ZoneClusterSearch.and("managedState", ZoneClusterSearch.entity().getManagedState(), Op.EQ);
         ZoneClusterSearch.done();
 
         ClusterIdSearch = createSearchBuilder(Long.class);
@@ -167,23 +171,17 @@ public List<HypervisorType> getAvailableHypervisorInZone(Long zoneId) {
             sc.setParameters("zoneId", zoneId);
         }
         List<ClusterVO> clusters = listBy(sc);
-        List<HypervisorType> hypers = new ArrayList<HypervisorType>(4);
+        List<HypervisorType> distinctHypervisors = new ArrayList<>(4);
         for (ClusterVO cluster : clusters) {
-            hypers.add(cluster.getHypervisorType());
+            distinctHypervisors.add(cluster.getHypervisorType());
         }
 
-        return hypers;
+        return distinctHypervisors;
     }
 
     @Override
-    public Set<HypervisorType> getDistictAvailableHypervisorsAcrossClusters() {
-        SearchCriteria<ClusterVO> sc = ClusterSearch.create();
-        List<ClusterVO> clusters = listBy(sc);
-        Set<HypervisorType> hypers = new HashSet<>();
-        for (ClusterVO cluster : clusters) {
-            hypers.add(cluster.getHypervisorType());
-        }
-        return hypers;
+    public Set<HypervisorType> getDistinctAvailableHypervisorsAcrossClusters() {
+        return new HashSet<>(getAvailableHypervisorInZone(null));
     }
 
     @Override
@@ -266,6 +264,23 @@ public List<Long> listClustersWithDisabledPods(long zoneId) {
         return customSearch(sc, null);
     }
 
+    @Override
+    public Integer countAllByDcId(long zoneId) {
+        SearchCriteria<ClusterVO> sc = ZoneClusterSearch.create();
+        sc.setParameters("dataCenterId", zoneId);
+        return getCount(sc);
+    }
+
+    @Override
+    public Integer countAllManagedAndEnabledByDcId(long zoneId) {
+        SearchCriteria<ClusterVO> sc = ZoneClusterSearch.create();
+        sc.setParameters("dataCenterId", zoneId);
+        sc.setParameters("allocationState", Grouping.AllocationState.Enabled);
+        sc.setParameters("managedState", Managed.ManagedState.Managed);
+
+        return getCount(sc);
+    }
+
     @Override
     public List<ClusterVO> listClustersByDcId(long zoneId) {
         SearchCriteria<ClusterVO> sc = ZoneClusterSearch.create();
@@ -289,7 +304,7 @@ public boolean remove(Long id) {
     }
 
     @Override
-    public List<Long> listAllClusters(Long zoneId) {
+    public List<Long> listAllClusterIds(Long zoneId) {
         SearchCriteria<Long> sc = ClusterIdSearch.create();
         if (zoneId != null) {
             sc.setParameters("dataCenterId", zoneId);
@@ -331,4 +346,12 @@ public List<ClusterVO> listClustersByArchAndZoneId(long zoneId, CPU.CPUArch arch
         sc.setParameters("arch", arch);
         return listBy(sc);
     }
+
+    @Override
+    public List<Long> listAllIds() {
+        GenericSearchBuilder<ClusterVO, Long> sb = createSearchBuilder(Long.class);
+        sb.selectFields(sb.entity().getId());
+        sb.done();
+        return customSearch(sb.create(), null);
+    }
 }
diff --git a/engine/schema/src/main/java/com/cloud/dc/dao/DataCenterIpAddressDaoImpl.java b/engine/schema/src/main/java/com/cloud/dc/dao/DataCenterIpAddressDaoImpl.java
index 48b9c83c64c6..ba01e31f80a8 100644
--- a/engine/schema/src/main/java/com/cloud/dc/dao/DataCenterIpAddressDaoImpl.java
+++ b/engine/schema/src/main/java/com/cloud/dc/dao/DataCenterIpAddressDaoImpl.java
@@ -294,8 +294,7 @@ public int countIpAddressUsage(final String ipAddress, final long podId, final l
         sc.addAnd("podId", SearchCriteria.Op.EQ, podId);
         sc.addAnd("dataCenterId", SearchCriteria.Op.EQ, dcId);
 
-        List<DataCenterIpAddressVO> result = listBy(sc);
-        return result.size();
+        return getCount(sc);
     }
 
     public DataCenterIpAddressDaoImpl() {
diff --git a/engine/schema/src/main/java/com/cloud/dc/dao/DataCenterVnetDaoImpl.java b/engine/schema/src/main/java/com/cloud/dc/dao/DataCenterVnetDaoImpl.java
index 1c29e6a944c6..ff6682497791 100644
--- a/engine/schema/src/main/java/com/cloud/dc/dao/DataCenterVnetDaoImpl.java
+++ b/engine/schema/src/main/java/com/cloud/dc/dao/DataCenterVnetDaoImpl.java
@@ -81,7 +81,7 @@ public List<DataCenterVnetVO> listAllocatedVnets(long physicalNetworkId) {
     public int countAllocatedVnets(long physicalNetworkId) {
         SearchCriteria<DataCenterVnetVO> sc = DcSearchAllocated.create();
         sc.setParameters("physicalNetworkId", physicalNetworkId);
-        return listBy(sc).size();
+        return getCount(sc);
     }
 
     @Override
diff --git a/engine/schema/src/main/java/com/cloud/domain/dao/DomainDetailsDaoImpl.java b/engine/schema/src/main/java/com/cloud/domain/dao/DomainDetailsDaoImpl.java
index b9721a2e58c5..2ecfd0ed1840 100644
--- a/engine/schema/src/main/java/com/cloud/domain/dao/DomainDetailsDaoImpl.java
+++ b/engine/schema/src/main/java/com/cloud/domain/dao/DomainDetailsDaoImpl.java
@@ -113,7 +113,7 @@ public String getConfigValue(long id, String key) {
         String enableDomainSettingsForChildDomain = _configDao.getValue("enable.domain.settings.for.child.domain");
         if (!Boolean.parseBoolean(enableDomainSettingsForChildDomain)) {
             vo = findDetail(id, key);
-            return vo == null ? null : getActualValue(vo);
+            return vo == null ? null : vo.getValue();
         }
         DomainVO domain = _domainDao.findById(id);
         // if value is not configured in domain then check its parent domain till ROOT
diff --git a/engine/schema/src/main/java/com/cloud/host/dao/HostDao.java b/engine/schema/src/main/java/com/cloud/host/dao/HostDao.java
index a2df6db44e51..5713e8ed7ae3 100644
--- a/engine/schema/src/main/java/com/cloud/host/dao/HostDao.java
+++ b/engine/schema/src/main/java/com/cloud/host/dao/HostDao.java
@@ -27,6 +27,7 @@
 import com.cloud.hypervisor.Hypervisor.HypervisorType;
 import com.cloud.info.RunningHostCountInfo;
 import com.cloud.resource.ResourceState;
+import com.cloud.utils.Pair;
 import com.cloud.utils.db.GenericDao;
 import com.cloud.utils.fsm.StateDao;
 
@@ -39,8 +40,14 @@ public interface HostDao extends GenericDao<HostVO, Long>, StateDao<Status, Stat
 
     Integer countAllByType(final Host.Type type);
 
+    Integer countAllInClusterByTypeAndStates(Long clusterId, final Host.Type type, List<Status> status);
+
     Integer countAllByTypeInZone(long zoneId, final Host.Type type);
 
+    Integer countUpAndEnabledHostsInZone(long zoneId);
+
+    Pair<Integer, Integer> countAllHostsAndCPUSocketsByType(Type type);
+
     /**
      * Mark all hosts associated with a certain management server
      * as disconnected.
@@ -75,32 +82,41 @@ public interface HostDao extends GenericDao<HostVO, Long>, StateDao<Status, Stat
 
     List<HostVO> findHypervisorHostInCluster(long clusterId);
 
+    HostVO findAnyStateHypervisorHostInCluster(long clusterId);
+
     HostVO findOldestExistentHypervisorHostInCluster(long clusterId);
 
     List<HostVO> listAllUpAndEnabledNonHAHosts(Type type, Long clusterId, Long podId, long dcId, String haTag);
 
     List<HostVO> findByDataCenterId(Long zoneId);
 
+    List<Long> listIdsByDataCenterId(Long zoneId);
+
     List<HostVO> findByPodId(Long podId);
 
+    List<Long> listIdsByPodId(Long podId);
+
     List<HostVO> findByClusterId(Long clusterId);
 
-    List<HostVO> findByClusterIdAndEncryptionSupport(Long clusterId);
+    List<Long> listIdsByClusterId(Long clusterId);
 
-    /**
-     * Returns hosts that are 'Up' and 'Enabled' from the given Data Center/Zone
-     */
-    List<HostVO> listByDataCenterId(long id);
+    List<Long> listIdsForUpRouting(Long zoneId, Long podId, Long clusterId);
+
+    List<Long> listIdsByType(Type type);
+
+    List<Long> listIdsForUpEnabledByZoneAndHypervisor(Long zoneId, HypervisorType hypervisorType);
+
+    List<HostVO> findByClusterIdAndEncryptionSupport(Long clusterId);
 
     /**
-     * Returns hosts that are from the given Data Center/Zone and at a given state (e.g. Creating, Enabled, Disabled, etc).
+     * Returns host Ids that are 'Up' and 'Enabled' from the given Data Center/Zone
      */
-    List<HostVO> listByDataCenterIdAndState(long id, ResourceState state);
+    List<Long> listEnabledIdsByDataCenterId(long id);
 
     /**
-     * Returns hosts that are 'Up' and 'Disabled' from the given Data Center/Zone
+     * Returns host Ids that are 'Up' and 'Disabled' from the given Data Center/Zone
      */
-    List<HostVO> listDisabledByDataCenterId(long id);
+    List<Long> listDisabledIdsByDataCenterId(long id);
 
     List<HostVO> listByDataCenterIdAndHypervisorType(long zoneId, Hypervisor.HypervisorType hypervisorType);
 
@@ -110,8 +126,6 @@ public interface HostDao extends GenericDao<HostVO, Long>, StateDao<Status, Stat
 
     List<HostVO> listAllHostsThatHaveNoRuleTag(Host.Type type, Long clusterId, Long podId, Long dcId);
 
-    List<HostVO> listAllHostsByType(Host.Type type);
-
     HostVO findByPublicIp(String publicIp);
 
     List<Long> listClustersByHostTag(String hostTagOnOffering);
@@ -171,4 +185,16 @@ public interface HostDao extends GenericDao<HostVO, Long>, StateDao<Status, Stat
     List<Long> findClustersThatMatchHostTagRule(String computeOfferingTags);
 
     List<Long> listSsvmHostsWithPendingMigrateJobsOrderedByJobCount();
+
+    boolean isHostUp(long hostId);
+
+    List<Long> findHostIdsByZoneClusterResourceStateTypeAndHypervisorType(final Long zoneId, final Long clusterId,
+            final List<ResourceState> resourceStates, final List<Type> types,
+            final List<Hypervisor.HypervisorType> hypervisorTypes);
+
+    List<Long> listAllIds();
+
+    List<HypervisorType> listDistinctHypervisorTypes(final Long zoneId);
+
+    List<HostVO> listByIds(final List<Long> ids);
 }
diff --git a/engine/schema/src/main/java/com/cloud/host/dao/HostDaoImpl.java b/engine/schema/src/main/java/com/cloud/host/dao/HostDaoImpl.java
index 63950294654c..44429aa34734 100644
--- a/engine/schema/src/main/java/com/cloud/host/dao/HostDaoImpl.java
+++ b/engine/schema/src/main/java/com/cloud/host/dao/HostDaoImpl.java
@@ -20,6 +20,7 @@
 import java.sql.ResultSet;
 import java.sql.SQLException;
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.Date;
 import java.util.HashMap;
 import java.util.HashSet;
@@ -45,8 +46,8 @@
 import com.cloud.dc.dao.ClusterDao;
 import com.cloud.gpu.dao.HostGpuGroupsDao;
 import com.cloud.gpu.dao.VGPUTypesDao;
-import com.cloud.host.Host;
 import com.cloud.host.DetailVO;
+import com.cloud.host.Host;
 import com.cloud.host.Host.Type;
 import com.cloud.host.HostTagVO;
 import com.cloud.host.HostVO;
@@ -59,6 +60,7 @@
 import com.cloud.org.Managed;
 import com.cloud.resource.ResourceState;
 import com.cloud.utils.DateUtil;
+import com.cloud.utils.Pair;
 import com.cloud.utils.db.Attribute;
 import com.cloud.utils.db.DB;
 import com.cloud.utils.db.Filter;
@@ -74,8 +76,6 @@
 import com.cloud.utils.db.UpdateBuilder;
 import com.cloud.utils.exception.CloudRuntimeException;
 
-import java.util.Arrays;
-
 @DB
 @TableGenerator(name = "host_req_sq", table = "op_host", pkColumnName = "id", valueColumnName = "sequence", allocationSize = 1)
 public class HostDaoImpl extends GenericDaoBase<HostVO, Long> implements HostDao { //FIXME: , ExternalIdDao {
@@ -98,6 +98,7 @@ public class HostDaoImpl extends GenericDaoBase<HostVO, Long> implements HostDao
 
     protected SearchBuilder<HostVO> TypePodDcStatusSearch;
 
+    protected SearchBuilder<HostVO> IdsSearch;
     protected SearchBuilder<HostVO> IdStatusSearch;
     protected SearchBuilder<HostVO> TypeDcSearch;
     protected SearchBuilder<HostVO> TypeDcStatusSearch;
@@ -124,6 +125,7 @@ public class HostDaoImpl extends GenericDaoBase<HostVO, Long> implements HostDao
     protected SearchBuilder<HostVO> UnmanagedApplianceSearch;
     protected SearchBuilder<HostVO> MaintenanceCountSearch;
     protected SearchBuilder<HostVO> HostTypeCountSearch;
+    protected SearchBuilder<HostVO> HostTypeClusterCountSearch;
     protected SearchBuilder<HostVO> ResponsibleMsCountSearch;
     protected SearchBuilder<HostVO> HostTypeZoneCountSearch;
     protected SearchBuilder<HostVO> ClusterStatusSearch;
@@ -136,8 +138,7 @@ public class HostDaoImpl extends GenericDaoBase<HostVO, Long> implements HostDao
     protected SearchBuilder<HostVO> ManagedRoutingServersSearch;
     protected SearchBuilder<HostVO> SecondaryStorageVMSearch;
 
-    protected GenericSearchBuilder<HostVO, Long> HostIdSearch;
-    protected GenericSearchBuilder<HostVO, Long> HostsInStatusSearch;
+    protected GenericSearchBuilder<HostVO, Long> HostsInStatusesSearch;
     protected GenericSearchBuilder<HostVO, Long> CountRoutingByDc;
     protected SearchBuilder<HostTransferMapVO> HostTransferSearch;
     protected SearchBuilder<ClusterVO> ClusterManagedSearch;
@@ -187,12 +188,21 @@ public void init() {
 
         HostTypeCountSearch = createSearchBuilder();
         HostTypeCountSearch.and("type", HostTypeCountSearch.entity().getType(), SearchCriteria.Op.EQ);
+        HostTypeCountSearch.and("zoneId", HostTypeCountSearch.entity().getDataCenterId(), SearchCriteria.Op.EQ);
+        HostTypeCountSearch.and("resourceState", HostTypeCountSearch.entity().getResourceState(), SearchCriteria.Op.EQ);
         HostTypeCountSearch.done();
 
         ResponsibleMsCountSearch = createSearchBuilder();
         ResponsibleMsCountSearch.and("managementServerId", ResponsibleMsCountSearch.entity().getManagementServerId(), SearchCriteria.Op.EQ);
         ResponsibleMsCountSearch.done();
 
+        HostTypeClusterCountSearch = createSearchBuilder();
+        HostTypeClusterCountSearch.and("cluster", HostTypeClusterCountSearch.entity().getClusterId(), SearchCriteria.Op.EQ);
+        HostTypeClusterCountSearch.and("type", HostTypeClusterCountSearch.entity().getType(), SearchCriteria.Op.EQ);
+        HostTypeClusterCountSearch.and("status", HostTypeClusterCountSearch.entity().getStatus(), SearchCriteria.Op.IN);
+        HostTypeClusterCountSearch.and("removed", HostTypeClusterCountSearch.entity().getRemoved(), SearchCriteria.Op.NULL);
+        HostTypeClusterCountSearch.done();
+
         HostTypeZoneCountSearch = createSearchBuilder();
         HostTypeZoneCountSearch.and("type", HostTypeZoneCountSearch.entity().getType(), SearchCriteria.Op.EQ);
         HostTypeZoneCountSearch.and("dc", HostTypeZoneCountSearch.entity().getDataCenterId(), SearchCriteria.Op.EQ);
@@ -240,6 +250,10 @@ public void init() {
         TypeClusterStatusSearch.and("resourceState", TypeClusterStatusSearch.entity().getResourceState(), SearchCriteria.Op.EQ);
         TypeClusterStatusSearch.done();
 
+        IdsSearch = createSearchBuilder();
+        IdsSearch.and("id", IdsSearch.entity().getId(), SearchCriteria.Op.IN);
+        IdsSearch.done();
+
         IdStatusSearch = createSearchBuilder();
         IdStatusSearch.and("id", IdStatusSearch.entity().getId(), SearchCriteria.Op.EQ);
         IdStatusSearch.and("states", IdStatusSearch.entity().getStatus(), SearchCriteria.Op.IN);
@@ -386,14 +400,14 @@ public void init() {
         AvailHypevisorInZone.groupBy(AvailHypevisorInZone.entity().getHypervisorType());
         AvailHypevisorInZone.done();
 
-        HostsInStatusSearch = createSearchBuilder(Long.class);
-        HostsInStatusSearch.selectFields(HostsInStatusSearch.entity().getId());
-        HostsInStatusSearch.and("dc", HostsInStatusSearch.entity().getDataCenterId(), Op.EQ);
-        HostsInStatusSearch.and("pod", HostsInStatusSearch.entity().getPodId(), Op.EQ);
-        HostsInStatusSearch.and("cluster", HostsInStatusSearch.entity().getClusterId(), Op.EQ);
-        HostsInStatusSearch.and("type", HostsInStatusSearch.entity().getType(), Op.EQ);
-        HostsInStatusSearch.and("statuses", HostsInStatusSearch.entity().getStatus(), Op.IN);
-        HostsInStatusSearch.done();
+        HostsInStatusesSearch = createSearchBuilder(Long.class);
+        HostsInStatusesSearch.selectFields(HostsInStatusesSearch.entity().getId());
+        HostsInStatusesSearch.and("dc", HostsInStatusesSearch.entity().getDataCenterId(), Op.EQ);
+        HostsInStatusesSearch.and("pod", HostsInStatusesSearch.entity().getPodId(), Op.EQ);
+        HostsInStatusesSearch.and("cluster", HostsInStatusesSearch.entity().getClusterId(), Op.EQ);
+        HostsInStatusesSearch.and("type", HostsInStatusesSearch.entity().getType(), Op.EQ);
+        HostsInStatusesSearch.and("statuses", HostsInStatusesSearch.entity().getStatus(), Op.IN);
+        HostsInStatusesSearch.done();
 
         CountRoutingByDc = createSearchBuilder(Long.class);
         CountRoutingByDc.select(null, Func.COUNT, null);
@@ -456,11 +470,6 @@ public void init() {
         HostsInClusterSearch.and("server", HostsInClusterSearch.entity().getManagementServerId(), SearchCriteria.Op.NNULL);
         HostsInClusterSearch.done();
 
-        HostIdSearch = createSearchBuilder(Long.class);
-        HostIdSearch.selectFields(HostIdSearch.entity().getId());
-        HostIdSearch.and("dataCenterId", HostIdSearch.entity().getDataCenterId(), Op.EQ);
-        HostIdSearch.done();
-
         searchBuilderFindByRuleTag = _hostTagsDao.createSearchBuilder();
         searchBuilderFindByRuleTag.and("is_tag_a_rule", searchBuilderFindByRuleTag.entity().getIsTagARule(), Op.EQ);
         searchBuilderFindByRuleTag.or("tagDoesNotExist", searchBuilderFindByRuleTag.entity().getIsTagARule(), Op.NULL);
@@ -492,8 +501,7 @@ public long countBy(long clusterId, ResourceState... states) {
         sc.setParameters("resourceState", (Object[])states);
         sc.setParameters("cluster", clusterId);
 
-        List<HostVO> hosts = listBy(sc);
-        return hosts.size();
+        return getCount(sc);
     }
 
     @Override
@@ -503,37 +511,63 @@ public Integer countAllByType(final Host.Type type) {
         return getCount(sc);
     }
 
+    @Override
+    public Integer countAllInClusterByTypeAndStates(Long clusterId, final Host.Type type, List<Status> status) {
+        SearchCriteria<HostVO> sc = HostTypeClusterCountSearch.create();
+        if (clusterId != null) {
+            sc.setParameters("cluster", clusterId);
+        }
+        if (type != null) {
+            sc.setParameters("type", type);
+        }
+        if (status != null) {
+            sc.setParameters("status", status.toArray());
+        }
+        return getCount(sc);
+    }
+
     @Override
     public Integer countAllByTypeInZone(long zoneId, Type type) {
         SearchCriteria<HostVO> sc = HostTypeCountSearch.create();
         sc.setParameters("type", type);
-        sc.setParameters("dc", zoneId);
+        sc.setParameters("zoneId", zoneId);
         return getCount(sc);
     }
 
     @Override
-    public List<HostVO> listByDataCenterId(long id) {
-        return listByDataCenterIdAndState(id, ResourceState.Enabled);
+    public Integer countUpAndEnabledHostsInZone(long zoneId) {
+        SearchCriteria<HostVO> sc = HostTypeCountSearch.create();
+        sc.setParameters("type", Type.Routing);
+        sc.setParameters("resourceState", ResourceState.Enabled);
+        sc.setParameters("zoneId", zoneId);
+        return getCount(sc);
     }
 
     @Override
-    public List<HostVO> listByDataCenterIdAndState(long id, ResourceState state) {
-        SearchCriteria<HostVO> sc = scHostsFromZoneUpRouting(id);
-        sc.setParameters("resourceState", state);
-        return listBy(sc);
+    public Pair<Integer, Integer> countAllHostsAndCPUSocketsByType(Type type) {
+        GenericSearchBuilder<HostVO, SumCount> sb = createSearchBuilder(SumCount.class);
+        sb.select("sum", Func.SUM, sb.entity().getCpuSockets());
+        sb.select("count", Func.COUNT, null);
+        sb.and("type", sb.entity().getType(), SearchCriteria.Op.EQ);
+        sb.done();
+        SearchCriteria<SumCount> sc = sb.create();
+        sc.setParameters("type", type);
+        SumCount result = customSearch(sc, null).get(0);
+        return new Pair<>((int)result.count, (int)result.sum);
+    }
+
+    private List<Long> listIdsForRoutingByZoneIdAndResourceState(long zoneId, ResourceState state) {
+        return listIdsBy(Type.Routing, Status.Up, state, null, zoneId, null, null);
     }
 
     @Override
-    public List<HostVO> listDisabledByDataCenterId(long id) {
-        return listByDataCenterIdAndState(id, ResourceState.Disabled);
+    public List<Long> listEnabledIdsByDataCenterId(long id) {
+        return listIdsForRoutingByZoneIdAndResourceState(id, ResourceState.Enabled);
     }
 
-    private SearchCriteria<HostVO> scHostsFromZoneUpRouting(long id) {
-        SearchCriteria<HostVO> sc = DcSearch.create();
-        sc.setParameters("dc", id);
-        sc.setParameters("status", Status.Up);
-        sc.setParameters("type", Host.Type.Routing);
-        return sc;
+    @Override
+    public List<Long> listDisabledIdsByDataCenterId(long id) {
+        return listIdsForRoutingByZoneIdAndResourceState(id, ResourceState.Disabled);
     }
 
     @Override
@@ -1178,6 +1212,11 @@ public List<HostVO> findByDataCenterId(Long zoneId) {
         return listBy(sc);
     }
 
+    @Override
+    public List<Long> listIdsByDataCenterId(Long zoneId) {
+        return listIdsBy(Type.Routing, null, null, null, zoneId, null, null);
+    }
+
     @Override
     public List<HostVO> findByPodId(Long podId) {
         SearchCriteria<HostVO> sc = PodSearch.create();
@@ -1185,6 +1224,11 @@ public List<HostVO> findByPodId(Long podId) {
         return listBy(sc);
     }
 
+    @Override
+    public List<Long> listIdsByPodId(Long podId) {
+        return listIdsBy(null, null, null, null, null, podId, null);
+    }
+
     @Override
     public List<HostVO> findByClusterId(Long clusterId) {
         SearchCriteria<HostVO> sc = ClusterSearch.create();
@@ -1192,6 +1236,63 @@ public List<HostVO> findByClusterId(Long clusterId) {
         return listBy(sc);
     }
 
+    private List<Long> listIdsBy(Host.Type type, Status status, ResourceState resourceState,
+             HypervisorType hypervisorType, Long zoneId, Long podId, Long clusterId) {
+        GenericSearchBuilder<HostVO, Long> sb = createSearchBuilder(Long.class);
+        sb.selectFields(sb.entity().getId());
+        sb.and("type", sb.entity().getType(), SearchCriteria.Op.EQ);
+        sb.and("status", sb.entity().getStatus(), SearchCriteria.Op.EQ);
+        sb.and("resourceState", sb.entity().getResourceState(), SearchCriteria.Op.EQ);
+        sb.and("hypervisorType", sb.entity().getHypervisorType(), SearchCriteria.Op.EQ);
+        sb.and("zoneId", sb.entity().getDataCenterId(), SearchCriteria.Op.EQ);
+        sb.and("podId", sb.entity().getPodId(), SearchCriteria.Op.EQ);
+        sb.and("clusterId", sb.entity().getClusterId(), SearchCriteria.Op.EQ);
+        sb.done();
+        SearchCriteria<Long> sc = sb.create();
+        if (type != null) {
+            sc.setParameters("type", type);
+        }
+        if (status != null) {
+            sc.setParameters("status", status);
+        }
+        if (resourceState != null) {
+            sc.setParameters("resourceState", resourceState);
+        }
+        if (hypervisorType != null) {
+            sc.setParameters("hypervisorType", hypervisorType);
+        }
+        if (zoneId != null) {
+            sc.setParameters("zoneId", zoneId);
+        }
+        if (podId != null) {
+            sc.setParameters("podId", podId);
+        }
+        if (clusterId != null) {
+            sc.setParameters("clusterId", clusterId);
+        }
+        return customSearch(sc, null);
+    }
+
+    @Override
+    public List<Long> listIdsByClusterId(Long clusterId) {
+        return listIdsBy(null, null, null, null, null, null, clusterId);
+    }
+
+    @Override
+    public List<Long> listIdsForUpRouting(Long zoneId, Long podId, Long clusterId) {
+        return listIdsBy(Type.Routing, Status.Up, null, null, zoneId, podId, clusterId);
+    }
+
+    @Override
+    public List<Long> listIdsByType(Type type) {
+        return listIdsBy(type, null, null, null, null, null, null);
+    }
+
+    @Override
+    public List<Long> listIdsForUpEnabledByZoneAndHypervisor(Long zoneId, HypervisorType hypervisorType) {
+        return listIdsBy(null, Status.Up, ResourceState.Enabled, hypervisorType, zoneId, null, null);
+    }
+
     @Override
     public List<HostVO> findByClusterIdAndEncryptionSupport(Long clusterId) {
         SearchBuilder<DetailVO> hostCapabilitySearch = _detailsDao.createSearchBuilder();
@@ -1244,6 +1345,15 @@ public List<HostVO> findHypervisorHostInCluster(long clusterId) {
         return listBy(sc);
     }
 
+    @Override
+    public HostVO findAnyStateHypervisorHostInCluster(long clusterId) {
+        SearchCriteria<HostVO> sc = TypeClusterStatusSearch.create();
+        sc.setParameters("type", Host.Type.Routing);
+        sc.setParameters("cluster", clusterId);
+        List<HostVO> list = listBy(sc, new Filter(1));
+        return list.isEmpty() ? null : list.get(0);
+    }
+
     @Override
     public HostVO findOldestExistentHypervisorHostInCluster(long clusterId) {
         SearchCriteria<HostVO> sc = TypeClusterStatusSearch.create();
@@ -1263,9 +1373,7 @@ public HostVO findOldestExistentHypervisorHostInCluster(long clusterId) {
 
     @Override
     public List<Long> listAllHosts(long zoneId) {
-        SearchCriteria<Long> sc = HostIdSearch.create();
-        sc.addAnd("dataCenterId", SearchCriteria.Op.EQ, zoneId);
-        return customSearch(sc, null);
+        return listIdsBy(null, null, null, null, zoneId, null, null);
     }
 
     @Override
@@ -1449,15 +1557,6 @@ public List<String> listOrderedHostsHypervisorVersionsInDatacenter(long datacent
         return result;
     }
 
-    @Override
-    public List<HostVO> listAllHostsByType(Host.Type type) {
-        SearchCriteria<HostVO> sc = TypeSearch.create();
-        sc.setParameters("type", type);
-        sc.setParameters("resourceState", ResourceState.Enabled);
-
-        return listBy(sc);
-    }
-
     @Override
     public List<HostVO> listByType(Host.Type type) {
         SearchCriteria<HostVO> sc = TypeSearch.create();
@@ -1602,4 +1701,75 @@ private String createSqlFindHostToExecuteCommand(boolean useDisabledHosts) {
         }
         return String.format(sqlFindHostInZoneToExecuteCommand, hostResourceStatus);
     }
+
+    @Override
+    public boolean isHostUp(long hostId) {
+        GenericSearchBuilder<HostVO, Status> sb = createSearchBuilder(Status.class);
+        sb.and("id", sb.entity().getId(), Op.EQ);
+        sb.selectFields(sb.entity().getStatus());
+        SearchCriteria<Status> sc = sb.create();
+        List<Status> statuses = customSearch(sc, null);
+        return CollectionUtils.isNotEmpty(statuses) && Status.Up.equals(statuses.get(0));
+    }
+
+    @Override
+    public List<Long> findHostIdsByZoneClusterResourceStateTypeAndHypervisorType(final Long zoneId, final Long clusterId,
+                final List<ResourceState> resourceStates, final List<Type> types,
+                final List<Hypervisor.HypervisorType> hypervisorTypes) {
+        GenericSearchBuilder<HostVO, Long> sb = createSearchBuilder(Long.class);
+        sb.selectFields(sb.entity().getId());
+        sb.and("zoneId", sb.entity().getDataCenterId(), SearchCriteria.Op.EQ);
+        sb.and("clusterId", sb.entity().getClusterId(), SearchCriteria.Op.EQ);
+        sb.and("resourceState", sb.entity().getResourceState(), SearchCriteria.Op.IN);
+        sb.and("type", sb.entity().getType(), SearchCriteria.Op.IN);
+        if (CollectionUtils.isNotEmpty(hypervisorTypes)) {
+            sb.and().op(sb.entity().getHypervisorType(), SearchCriteria.Op.NULL);
+            sb.or("hypervisorTypes", sb.entity().getHypervisorType(), SearchCriteria.Op.IN);
+            sb.cp();
+        }
+        sb.done();
+        SearchCriteria<Long> sc = sb.create();
+        if (zoneId != null) {
+            sc.setParameters("zoneId", zoneId);
+        }
+        if (clusterId != null) {
+            sc.setParameters("clusterId", clusterId);
+        }
+        if (CollectionUtils.isNotEmpty(hypervisorTypes)) {
+            sc.setParameters("hypervisorTypes", hypervisorTypes.toArray());
+        }
+        sc.setParameters("resourceState", resourceStates.toArray());
+        sc.setParameters("type", types.toArray());
+        return customSearch(sc, null);
+    }
+
+    @Override
+    public List<Long> listAllIds() {
+        return listIdsBy(null, null, null, null, null, null, null);
+    }
+
+    @Override
+    public List<HypervisorType> listDistinctHypervisorTypes(final Long zoneId) {
+        GenericSearchBuilder<HostVO, HypervisorType> sb = createSearchBuilder(HypervisorType.class);
+        sb.and("zoneId", sb.entity().getDataCenterId(), SearchCriteria.Op.EQ);
+        sb.and("type", sb.entity().getType(), SearchCriteria.Op.EQ);
+        sb.select(null, Func.DISTINCT, sb.entity().getHypervisorType());
+        sb.done();
+        SearchCriteria<HypervisorType> sc = sb.create();
+        if (zoneId != null) {
+            sc.setParameters("zoneId", zoneId);
+        }
+        sc.setParameters("type", Type.Routing);
+        return customSearch(sc, null);
+    }
+
+    @Override
+    public List<HostVO> listByIds(List<Long> ids) {
+        if (CollectionUtils.isEmpty(ids)) {
+            return new ArrayList<>();
+        }
+        SearchCriteria<HostVO> sc = IdsSearch.create();
+        sc.setParameters("id", ids.toArray());
+        return search(sc, null);
+    }
 }
diff --git a/engine/schema/src/main/java/com/cloud/network/dao/IPAddressDaoImpl.java b/engine/schema/src/main/java/com/cloud/network/dao/IPAddressDaoImpl.java
index aa143838c343..5499d04e3a1f 100644
--- a/engine/schema/src/main/java/com/cloud/network/dao/IPAddressDaoImpl.java
+++ b/engine/schema/src/main/java/com/cloud/network/dao/IPAddressDaoImpl.java
@@ -421,7 +421,7 @@ public long countFreePublicIPs() {
     public long countFreeIpsInVlan(long vlanDbId) {
         SearchCriteria<IPAddressVO> sc = VlanDbIdSearchUnallocated.create();
         sc.setParameters("vlanDbId", vlanDbId);
-        return listBy(sc).size();
+        return getCount(sc);
     }
 
     @Override
diff --git a/engine/schema/src/main/java/com/cloud/network/dao/NetworkDaoImpl.java b/engine/schema/src/main/java/com/cloud/network/dao/NetworkDaoImpl.java
index fa448b026e45..0aae532eac57 100644
--- a/engine/schema/src/main/java/com/cloud/network/dao/NetworkDaoImpl.java
+++ b/engine/schema/src/main/java/com/cloud/network/dao/NetworkDaoImpl.java
@@ -415,8 +415,7 @@ public int getOtherPersistentNetworksCount(long id, String broadcastURI, boolean
         sc.setParameters("broadcastUri", broadcastURI);
         sc.setParameters("guestType", guestTypes);
         sc.setJoinParameters("persistent", "persistent", isPersistent);
-        List<NetworkVO> persistentNetworks = search(sc, null);
-        return persistentNetworks.size();
+        return getCount(sc);
     }
 
     @Override
diff --git a/engine/schema/src/main/java/com/cloud/secstorage/CommandExecLogDaoImpl.java b/engine/schema/src/main/java/com/cloud/secstorage/CommandExecLogDaoImpl.java
index a37acdf60298..8229c3a62fc2 100644
--- a/engine/schema/src/main/java/com/cloud/secstorage/CommandExecLogDaoImpl.java
+++ b/engine/schema/src/main/java/com/cloud/secstorage/CommandExecLogDaoImpl.java
@@ -55,8 +55,7 @@ public Integer getCopyCmdCountForSSVM(Long id) {
         SearchCriteria<CommandExecLogVO> sc = CommandSearch.create();
         sc.setParameters("host_id", id);
         sc.setParameters("command_name", "CopyCommand");
-        List<CommandExecLogVO> copyCmds = customSearch(sc, null);
-        return copyCmds.size();
+        return getCount(sc);
     }
 
     @Override
diff --git a/engine/schema/src/main/java/com/cloud/service/dao/ServiceOfferingDao.java b/engine/schema/src/main/java/com/cloud/service/dao/ServiceOfferingDao.java
index 48e63d8e2b55..ceb5b0a4fc1c 100644
--- a/engine/schema/src/main/java/com/cloud/service/dao/ServiceOfferingDao.java
+++ b/engine/schema/src/main/java/com/cloud/service/dao/ServiceOfferingDao.java
@@ -54,7 +54,7 @@ List<ServiceOfferingVO> createSystemServiceOfferings(String name, String uniqueN
 
     List<ServiceOfferingVO> listPublicByCpuAndMemory(Integer cpus, Integer memory);
 
-    List<ServiceOfferingVO> listByHostTag(String tag);
-
     ServiceOfferingVO findServiceOfferingByComputeOnlyDiskOffering(long diskOfferingId, boolean includingRemoved);
+
+    List<Long> listIdsByHostTag(String tag);
 }
diff --git a/engine/schema/src/main/java/com/cloud/service/dao/ServiceOfferingDaoImpl.java b/engine/schema/src/main/java/com/cloud/service/dao/ServiceOfferingDaoImpl.java
index 706dcdc1b7b5..803522fa6aa6 100644
--- a/engine/schema/src/main/java/com/cloud/service/dao/ServiceOfferingDaoImpl.java
+++ b/engine/schema/src/main/java/com/cloud/service/dao/ServiceOfferingDaoImpl.java
@@ -34,6 +34,7 @@
 import com.cloud.storage.Storage.ProvisioningType;
 import com.cloud.utils.db.DB;
 import com.cloud.utils.db.GenericDaoBase;
+import com.cloud.utils.db.GenericSearchBuilder;
 import com.cloud.utils.db.SearchBuilder;
 import com.cloud.utils.db.SearchCriteria;
 import com.cloud.utils.exception.CloudRuntimeException;
@@ -293,8 +294,9 @@ public ServiceOfferingVO findServiceOfferingByComputeOnlyDiskOffering(long diskO
     }
 
     @Override
-    public List<ServiceOfferingVO> listByHostTag(String tag) {
-        SearchBuilder<ServiceOfferingVO> sb = createSearchBuilder();
+    public List<Long> listIdsByHostTag(String tag) {
+        GenericSearchBuilder<ServiceOfferingVO, Long> sb = createSearchBuilder(Long.class);
+        sb.selectFields(sb.entity().getId());
         sb.and("tagNotNull", sb.entity().getHostTag(), SearchCriteria.Op.NNULL);
         sb.and().op("tagEq", sb.entity().getHostTag(), SearchCriteria.Op.EQ);
         sb.or("tagStartLike", sb.entity().getHostTag(), SearchCriteria.Op.LIKE);
@@ -302,11 +304,12 @@ public List<ServiceOfferingVO> listByHostTag(String tag) {
         sb.or("tagEndLike", sb.entity().getHostTag(), SearchCriteria.Op.LIKE);
         sb.cp();
         sb.done();
-        SearchCriteria<ServiceOfferingVO> sc = sb.create();
+        SearchCriteria<Long> sc = sb.create();
+
         sc.setParameters("tagEq", tag);
         sc.setParameters("tagStartLike", tag + ",%");
         sc.setParameters("tagMidLike", "%," + tag + ",%");
         sc.setParameters("tagEndLike",   "%," + tag);
-        return listBy(sc);
+        return customSearch(sc, null);
     }
 }
diff --git a/engine/schema/src/main/java/com/cloud/storage/dao/StoragePoolHostDao.java b/engine/schema/src/main/java/com/cloud/storage/dao/StoragePoolHostDao.java
index 62ef5b7570d1..639c2571541d 100644
--- a/engine/schema/src/main/java/com/cloud/storage/dao/StoragePoolHostDao.java
+++ b/engine/schema/src/main/java/com/cloud/storage/dao/StoragePoolHostDao.java
@@ -34,7 +34,7 @@ public interface StoragePoolHostDao extends GenericDao<StoragePoolHostVO, Long>
 
     List<Long> findHostsConnectedToPools(List<Long> poolIds);
 
-    List<Pair<Long, Integer>> getDatacenterStoragePoolHostInfo(long dcId, boolean sharedOnly);
+    boolean hasDatacenterStoragePoolHostInfo(long dcId, boolean sharedOnly);
 
     public void deletePrimaryRecordsForHost(long hostId);
 
diff --git a/engine/schema/src/main/java/com/cloud/storage/dao/StoragePoolHostDaoImpl.java b/engine/schema/src/main/java/com/cloud/storage/dao/StoragePoolHostDaoImpl.java
index 987a42f410e7..5a466af348c3 100644
--- a/engine/schema/src/main/java/com/cloud/storage/dao/StoragePoolHostDaoImpl.java
+++ b/engine/schema/src/main/java/com/cloud/storage/dao/StoragePoolHostDaoImpl.java
@@ -55,11 +55,11 @@ public class StoragePoolHostDaoImpl extends GenericDaoBase<StoragePoolHostVO, Lo
 
     protected static final String HOSTS_FOR_POOLS_SEARCH = "SELECT DISTINCT(ph.host_id) FROM storage_pool_host_ref ph, host h WHERE ph.host_id = h.id AND h.status = 'Up' AND resource_state = 'Enabled' AND ph.pool_id IN (?)";
 
-    protected static final String STORAGE_POOL_HOST_INFO = "SELECT p.data_center_id,  count(ph.host_id) " + " FROM storage_pool p, storage_pool_host_ref ph "
-        + " WHERE p.id = ph.pool_id AND p.data_center_id = ? " + " GROUP by p.data_center_id";
+    protected static final String STORAGE_POOL_HOST_INFO = "SELECT (SELECT id FROM storage_pool_host_ref ph WHERE " +
+            "ph.pool_id=p.id limit 1) AS sphr FROM storage_pool p WHERE p.data_center_id = ?";
 
-    protected static final String SHARED_STORAGE_POOL_HOST_INFO = "SELECT p.data_center_id,  count(ph.host_id) " + " FROM storage_pool p, storage_pool_host_ref ph "
-        + " WHERE p.id = ph.pool_id AND p.data_center_id = ? " + " AND p.pool_type NOT IN ('LVM', 'Filesystem')" + " GROUP by p.data_center_id";
+    protected static final String SHARED_STORAGE_POOL_HOST_INFO = "SELECT (SELECT id FROM storage_pool_host_ref ph " +
+            "WHERE ph.pool_id=p.id limit 1) AS sphr FROM storage_pool p WHERE p.data_center_id = ? AND p.pool_type NOT IN ('LVM', 'Filesystem')";
 
     protected static final String DELETE_PRIMARY_RECORDS = "DELETE " + "FROM storage_pool_host_ref " + "WHERE host_id = ?";
 
@@ -169,23 +169,23 @@ public List<Long> findHostsConnectedToPools(List<Long> poolIds) {
     }
 
     @Override
-    public List<Pair<Long, Integer>> getDatacenterStoragePoolHostInfo(long dcId, boolean sharedOnly) {
-        ArrayList<Pair<Long, Integer>> l = new ArrayList<Pair<Long, Integer>>();
+    public boolean hasDatacenterStoragePoolHostInfo(long dcId, boolean sharedOnly) {
+        Long poolCount = 0L;
         String sql = sharedOnly ? SHARED_STORAGE_POOL_HOST_INFO : STORAGE_POOL_HOST_INFO;
         TransactionLegacy txn = TransactionLegacy.currentTxn();
-        PreparedStatement pstmt = null;
-        try {
-            pstmt = txn.prepareAutoCloseStatement(sql);
+        try (PreparedStatement pstmt = txn.prepareAutoCloseStatement(sql)) {
             pstmt.setLong(1, dcId);
-
             ResultSet rs = pstmt.executeQuery();
             while (rs.next()) {
-                l.add(new Pair<Long, Integer>(rs.getLong(1), rs.getInt(2)));
+                poolCount = rs.getLong(1);
+                if (poolCount > 0) {
+                    return true;
+                }
             }
         } catch (SQLException e) {
             logger.debug("SQLException: ", e);
         }
-        return l;
+        return false;
     }
 
     /**
diff --git a/engine/schema/src/main/java/com/cloud/storage/dao/VMTemplateDao.java b/engine/schema/src/main/java/com/cloud/storage/dao/VMTemplateDao.java
index 1c5a2cb4256a..3ac514530ced 100644
--- a/engine/schema/src/main/java/com/cloud/storage/dao/VMTemplateDao.java
+++ b/engine/schema/src/main/java/com/cloud/storage/dao/VMTemplateDao.java
@@ -67,6 +67,8 @@ public interface VMTemplateDao extends GenericDao<VMTemplateVO, Long>, StateDao<
 
     public List<VMTemplateVO> userIsoSearch(boolean listRemoved);
 
+    List<VMTemplateVO> listAllReadySystemVMTemplates(Long zoneId);
+
     VMTemplateVO findSystemVMTemplate(long zoneId);
 
     VMTemplateVO findSystemVMReadyTemplate(long zoneId, HypervisorType hypervisorType);
@@ -91,6 +93,5 @@ public interface VMTemplateDao extends GenericDao<VMTemplateVO, Long>, StateDao<
 
     List<VMTemplateVO> listByIds(List<Long> ids);
 
-    List<VMTemplateVO> listByTemplateTag(String tag);
-
+    List<Long> listIdsByTemplateTag(String tag);
 }
diff --git a/engine/schema/src/main/java/com/cloud/storage/dao/VMTemplateDaoImpl.java b/engine/schema/src/main/java/com/cloud/storage/dao/VMTemplateDaoImpl.java
index 4665f6602512..7513848536b2 100644
--- a/engine/schema/src/main/java/com/cloud/storage/dao/VMTemplateDaoImpl.java
+++ b/engine/schema/src/main/java/com/cloud/storage/dao/VMTemplateDaoImpl.java
@@ -344,19 +344,12 @@ public boolean configure(String name, Map<String, Object> params) throws Configu
         readySystemTemplateSearch = createSearchBuilder();
         readySystemTemplateSearch.and("state", readySystemTemplateSearch.entity().getState(), SearchCriteria.Op.EQ);
         readySystemTemplateSearch.and("templateType", readySystemTemplateSearch.entity().getTemplateType(), SearchCriteria.Op.EQ);
+        readySystemTemplateSearch.and("hypervisorType", readySystemTemplateSearch.entity().getHypervisorType(), SearchCriteria.Op.IN);
         SearchBuilder<TemplateDataStoreVO> templateDownloadSearch = _templateDataStoreDao.createSearchBuilder();
         templateDownloadSearch.and("downloadState", templateDownloadSearch.entity().getDownloadState(), SearchCriteria.Op.IN);
         readySystemTemplateSearch.join("vmTemplateJoinTemplateStoreRef", templateDownloadSearch, templateDownloadSearch.entity().getTemplateId(),
             readySystemTemplateSearch.entity().getId(), JoinBuilder.JoinType.INNER);
-        SearchBuilder<HostVO> hostHyperSearch2 = _hostDao.createSearchBuilder();
-        hostHyperSearch2.and("type", hostHyperSearch2.entity().getType(), SearchCriteria.Op.EQ);
-        hostHyperSearch2.and("zoneId", hostHyperSearch2.entity().getDataCenterId(), SearchCriteria.Op.EQ);
-        hostHyperSearch2.and("removed", hostHyperSearch2.entity().getRemoved(), SearchCriteria.Op.NULL);
-        hostHyperSearch2.groupBy(hostHyperSearch2.entity().getHypervisorType());
-
-        readySystemTemplateSearch.join("tmplHyper", hostHyperSearch2, hostHyperSearch2.entity().getHypervisorType(), readySystemTemplateSearch.entity()
-            .getHypervisorType(), JoinBuilder.JoinType.INNER);
-        hostHyperSearch2.done();
+        readySystemTemplateSearch.groupBy(readySystemTemplateSearch.entity().getId());
         readySystemTemplateSearch.done();
 
         tmpltTypeHyperSearch2 = createSearchBuilder();
@@ -556,29 +549,35 @@ public VMTemplateVO findSystemVMTemplate(long zoneId) {
     }
 
     @Override
-    public VMTemplateVO findSystemVMReadyTemplate(long zoneId, HypervisorType hypervisorType) {
+    public List<VMTemplateVO> listAllReadySystemVMTemplates(Long zoneId) {
+        List<HypervisorType> availableHypervisors = _hostDao.listDistinctHypervisorTypes(zoneId);
+        if (CollectionUtils.isEmpty(availableHypervisors)) {
+            return Collections.emptyList();
+        }
         SearchCriteria<VMTemplateVO> sc = readySystemTemplateSearch.create();
         sc.setParameters("templateType", Storage.TemplateType.SYSTEM);
         sc.setParameters("state", VirtualMachineTemplate.State.Active);
-        sc.setJoinParameters("tmplHyper", "type", Host.Type.Routing);
-        sc.setJoinParameters("tmplHyper", "zoneId", zoneId);
-        sc.setJoinParameters("vmTemplateJoinTemplateStoreRef", "downloadState", new VMTemplateStorageResourceAssoc.Status[] {VMTemplateStorageResourceAssoc.Status.DOWNLOADED, VMTemplateStorageResourceAssoc.Status.BYPASSED});
-
+        sc.setParameters("hypervisorType", availableHypervisors.toArray());
+        sc.setJoinParameters("vmTemplateJoinTemplateStoreRef", "downloadState",
+                List.of(VMTemplateStorageResourceAssoc.Status.DOWNLOADED,
+                        VMTemplateStorageResourceAssoc.Status.BYPASSED).toArray());
         // order by descending order of id
-        List<VMTemplateVO> tmplts = listBy(sc, new Filter(VMTemplateVO.class, "id", false, null, null));
-
-        if (tmplts.size() > 0) {
-            if (hypervisorType == HypervisorType.Any) {
-                return tmplts.get(0);
-            }
-            for (VMTemplateVO tmplt : tmplts) {
-                if (tmplt.getHypervisorType() == hypervisorType) {
-                    return tmplt;
-                }
-            }
+        return listBy(sc, new Filter(VMTemplateVO.class, "id", false, null, null));
+    }
 
+    @Override
+    public VMTemplateVO findSystemVMReadyTemplate(long zoneId, HypervisorType hypervisorType) {
+        List<VMTemplateVO> templates = listAllReadySystemVMTemplates(zoneId);
+        if (CollectionUtils.isEmpty(templates)) {
+            return null;
         }
-        return null;
+        if (hypervisorType == HypervisorType.Any) {
+            return templates.get(0);
+        }
+        return templates.stream()
+                .filter(t -> t.getHypervisorType() == hypervisorType)
+                .findFirst()
+                .orElse(null);
     }
 
     @Override
@@ -687,13 +686,14 @@ public boolean remove(Long id) {
     }
 
     @Override
-    public List<VMTemplateVO> listByTemplateTag(String tag) {
-        SearchBuilder<VMTemplateVO> sb = createSearchBuilder();
+    public List<Long> listIdsByTemplateTag(String tag) {
+        GenericSearchBuilder<VMTemplateVO, Long> sb = createSearchBuilder(Long.class);
+        sb.selectFields(sb.entity().getId());
         sb.and("tag", sb.entity().getTemplateTag(), SearchCriteria.Op.EQ);
         sb.done();
-        SearchCriteria<VMTemplateVO> sc = sb.create();
+        SearchCriteria<Long> sc = sb.create();
         sc.setParameters("tag", tag);
-        return listIncludingRemovedBy(sc);
+        return customSearchIncludingRemoved(sc, null);
     }
 
     @Override
diff --git a/engine/schema/src/main/java/com/cloud/storage/dao/VolumeDaoImpl.java b/engine/schema/src/main/java/com/cloud/storage/dao/VolumeDaoImpl.java
index 0c4d707635aa..750dbf2bee0f 100644
--- a/engine/schema/src/main/java/com/cloud/storage/dao/VolumeDaoImpl.java
+++ b/engine/schema/src/main/java/com/cloud/storage/dao/VolumeDaoImpl.java
@@ -571,14 +571,6 @@ public long secondaryStorageUsedForAccount(long accountId) {
         }
     }
 
-    public static class SumCount {
-        public long sum;
-        public long count;
-
-        public SumCount() {
-        }
-    }
-
     @Override
     public List<VolumeVO> listVolumesToBeDestroyed() {
         SearchCriteria<VolumeVO> sc = AllFieldsSearch.create();
diff --git a/engine/schema/src/main/java/com/cloud/upgrade/SystemVmTemplateRegistration.java b/engine/schema/src/main/java/com/cloud/upgrade/SystemVmTemplateRegistration.java
index 7314937ff5b2..f9f973f45cf9 100644
--- a/engine/schema/src/main/java/com/cloud/upgrade/SystemVmTemplateRegistration.java
+++ b/engine/schema/src/main/java/com/cloud/upgrade/SystemVmTemplateRegistration.java
@@ -861,7 +861,7 @@ public void updateSystemVmTemplates(final Connection conn) {
             public void doInTransactionWithoutResult(final TransactionStatus status) {
                 Set<Hypervisor.HypervisorType> hypervisorsListInUse = new HashSet<Hypervisor.HypervisorType>();
                 try {
-                    hypervisorsListInUse = clusterDao.getDistictAvailableHypervisorsAcrossClusters();
+                    hypervisorsListInUse = clusterDao.getDistinctAvailableHypervisorsAcrossClusters();
 
                 } catch (final Exception e) {
                     LOGGER.error("updateSystemVmTemplates: Exception caught while getting hypervisor types from clusters: " + e.getMessage());
diff --git a/engine/schema/src/main/java/com/cloud/upgrade/dao/DatabaseAccessObject.java b/engine/schema/src/main/java/com/cloud/upgrade/dao/DatabaseAccessObject.java
index 1c2c4b3c7ce7..0b973d195deb 100644
--- a/engine/schema/src/main/java/com/cloud/upgrade/dao/DatabaseAccessObject.java
+++ b/engine/schema/src/main/java/com/cloud/upgrade/dao/DatabaseAccessObject.java
@@ -114,6 +114,17 @@ public void createIndex(Connection conn, String tableName, String indexName, Str
         }
     }
 
+    public void renameIndex(Connection conn, String tableName, String oldName, String newName) {
+        String stmt = String.format("ALTER TABLE %s RENAME INDEX %s TO %s", tableName, oldName, newName);
+        logger.debug("Statement: {}", stmt);
+        try (PreparedStatement pstmt = conn.prepareStatement(stmt)) {
+            pstmt.execute();
+            logger.debug("Renamed index {} to {}", oldName, newName);
+        } catch (SQLException e) {
+            logger.warn("Unable to rename index {} to {}", oldName, newName, e);
+        }
+    }
+
     protected void closePreparedStatement(PreparedStatement pstmt, String errorMessage) {
         try {
             if (pstmt != null) {
diff --git a/engine/schema/src/main/java/com/cloud/upgrade/dao/DbUpgradeUtils.java b/engine/schema/src/main/java/com/cloud/upgrade/dao/DbUpgradeUtils.java
index 51e6ac7b9a1d..2f90422adf8b 100644
--- a/engine/schema/src/main/java/com/cloud/upgrade/dao/DbUpgradeUtils.java
+++ b/engine/schema/src/main/java/com/cloud/upgrade/dao/DbUpgradeUtils.java
@@ -31,6 +31,12 @@ public static void addIndexIfNeeded(Connection conn, String tableName, String...
         }
     }
 
+    public static void renameIndexIfNeeded(Connection conn, String tableName, String oldName, String newName) {
+        if (!dao.indexExists(conn, tableName, oldName)) {
+            dao.renameIndex(conn, tableName, oldName, newName);
+        }
+    }
+
     public static void addForeignKey(Connection conn, String tableName, String tableColumn, String foreignTableName, String foreignColumnName) {
         dao.addForeignKey(conn, tableName, tableColumn, foreignTableName, foreignColumnName);
     }
diff --git a/engine/schema/src/main/java/com/cloud/upgrade/dao/Upgrade41910to42000.java b/engine/schema/src/main/java/com/cloud/upgrade/dao/Upgrade41910to42000.java
index 4c26c6bde50b..5ce6b3abe918 100644
--- a/engine/schema/src/main/java/com/cloud/upgrade/dao/Upgrade41910to42000.java
+++ b/engine/schema/src/main/java/com/cloud/upgrade/dao/Upgrade41910to42000.java
@@ -58,6 +58,7 @@ public InputStream[] getPrepareScripts() {
     @Override
     public void performDataMigration(Connection conn) {
         checkAndUpdateAffinityGroupNameCharSetToUtf8mb4(conn);
+        addIndexes(conn);
     }
 
     @Override
@@ -113,4 +114,42 @@ private void checkAndUpdateAffinityGroupNameCharSetToUtf8mb4(Connection conn) {
             logger.warn("Exception while updating char set for affinity group name to utf8mb4: " + e.getMessage());
         }
     }
+
+    private void addIndexes(Connection conn) {
+        DbUpgradeUtils.addIndexIfNeeded(conn, "host", "mgmt_server_id");
+        DbUpgradeUtils.addIndexIfNeeded(conn, "host", "resource");
+        DbUpgradeUtils.addIndexIfNeeded(conn, "host", "resource_state");
+        DbUpgradeUtils.addIndexIfNeeded(conn, "host", "type");
+
+        DbUpgradeUtils.renameIndexIfNeeded(conn, "user_ip_address", "public_ip_address", "uk_public_ip_address");
+        DbUpgradeUtils.addIndexIfNeeded(conn, "user_ip_address", "public_ip_address");
+        DbUpgradeUtils.addIndexIfNeeded(conn, "user_ip_address", "data_center_id");
+        DbUpgradeUtils.addIndexIfNeeded(conn, "user_ip_address", "vlan_db_id");
+        DbUpgradeUtils.addIndexIfNeeded(conn, "user_ip_address", "removed");
+
+        DbUpgradeUtils.addIndexIfNeeded(conn, "vlan", "vlan_type");
+        DbUpgradeUtils.addIndexIfNeeded(conn, "vlan", "data_center_id");
+        DbUpgradeUtils.addIndexIfNeeded(conn, "vlan", "removed");
+
+        DbUpgradeUtils.addIndexIfNeeded(conn, "network_offering_details", "name");
+
+        DbUpgradeUtils.addIndexIfNeeded(conn, "network_offering_details", "resource_id", "resource_type");
+
+        DbUpgradeUtils.addIndexIfNeeded(conn, "service_offering", "cpu");
+        DbUpgradeUtils.addIndexIfNeeded(conn, "service_offering", "speed");
+        DbUpgradeUtils.addIndexIfNeeded(conn, "service_offering", "ram_size");
+
+        DbUpgradeUtils.addIndexIfNeeded(conn, "op_host_planner_reservation", "resource_usage");
+
+        DbUpgradeUtils.addIndexIfNeeded(conn, "storage_pool", "pool_type");
+        DbUpgradeUtils.addIndexIfNeeded(conn, "storage_pool", "data_center_id", "status", "scope", "hypervisor");
+
+        DbUpgradeUtils.addIndexIfNeeded(conn, "router_network_ref", "guest_type");
+
+        DbUpgradeUtils.addIndexIfNeeded(conn, "domain_router", "role");
+
+        DbUpgradeUtils.addIndexIfNeeded(conn, "async_job", "instance_type", "job_status");
+
+        DbUpgradeUtils.addIndexIfNeeded(conn, "cluster", "managed_state");
+    }
 }
diff --git a/engine/schema/src/main/java/com/cloud/vm/dao/ConsoleProxyDao.java b/engine/schema/src/main/java/com/cloud/vm/dao/ConsoleProxyDao.java
index cb19748fda46..af32163b4c70 100644
--- a/engine/schema/src/main/java/com/cloud/vm/dao/ConsoleProxyDao.java
+++ b/engine/schema/src/main/java/com/cloud/vm/dao/ConsoleProxyDao.java
@@ -45,7 +45,7 @@ public interface ConsoleProxyDao extends GenericDao<ConsoleProxyVO, Long> {
 
     public List<ConsoleProxyLoadInfo> getDatacenterSessionLoadMatrix();
 
-    public List<Pair<Long, Integer>> getDatacenterStoragePoolHostInfo(long dcId, boolean countAllPoolTypes);
+    public boolean hasDatacenterStoragePoolHostInfo(long dcId, boolean sharedOnly);
 
     public List<Pair<Long, Integer>> getProxyLoadMatrix();
 
diff --git a/engine/schema/src/main/java/com/cloud/vm/dao/ConsoleProxyDaoImpl.java b/engine/schema/src/main/java/com/cloud/vm/dao/ConsoleProxyDaoImpl.java
index ef94a4d9f72e..bc79194a10fd 100644
--- a/engine/schema/src/main/java/com/cloud/vm/dao/ConsoleProxyDaoImpl.java
+++ b/engine/schema/src/main/java/com/cloud/vm/dao/ConsoleProxyDaoImpl.java
@@ -23,7 +23,6 @@
 import java.util.Date;
 import java.util.List;
 
-
 import org.springframework.stereotype.Component;
 
 import com.cloud.info.ConsoleProxyLoadInfo;
@@ -76,11 +75,11 @@ public class ConsoleProxyDaoImpl extends GenericDaoBase<ConsoleProxyVO, Long> im
 
     private static final String GET_PROXY_ACTIVE_LOAD = "SELECT active_session AS count" + " FROM console_proxy" + " WHERE id=?";
 
-    private static final String STORAGE_POOL_HOST_INFO = "SELECT p.data_center_id,  count(ph.host_id) " + " FROM storage_pool p, storage_pool_host_ref ph "
-        + " WHERE p.id = ph.pool_id AND p.data_center_id = ? " + " GROUP by p.data_center_id";
+    protected static final String STORAGE_POOL_HOST_INFO = "SELECT (SELECT id FROM storage_pool_host_ref ph WHERE " +
+            "ph.pool_id=p.id limit 1) AS sphr FROM storage_pool p WHERE p.data_center_id = ?";
 
-    private static final String SHARED_STORAGE_POOL_HOST_INFO = "SELECT p.data_center_id,  count(ph.host_id) " + " FROM storage_pool p, storage_pool_host_ref ph "
-        + " WHERE p.pool_type <> 'LVM' AND p.id = ph.pool_id AND p.data_center_id = ? " + " GROUP by p.data_center_id";
+    protected static final String SHARED_STORAGE_POOL_HOST_INFO = "SELECT (SELECT id FROM storage_pool_host_ref ph " +
+            "WHERE ph.pool_id=p.id limit 1) AS sphr FROM storage_pool p WHERE p.data_center_id = ? AND p.pool_type NOT IN ('LVM', 'Filesystem')";
 
     protected SearchBuilder<ConsoleProxyVO> DataCenterStatusSearch;
     protected SearchBuilder<ConsoleProxyVO> StateSearch;
@@ -219,28 +218,23 @@ public List<Pair<Long, Integer>> getProxyLoadMatrix() {
     }
 
     @Override
-    public List<Pair<Long, Integer>> getDatacenterStoragePoolHostInfo(long dcId, boolean countAllPoolTypes) {
-        ArrayList<Pair<Long, Integer>> l = new ArrayList<Pair<Long, Integer>>();
-
+    public boolean hasDatacenterStoragePoolHostInfo(long dcId, boolean sharedOnly) {
+        Long poolCount = 0L;
+        String sql = sharedOnly ? SHARED_STORAGE_POOL_HOST_INFO : STORAGE_POOL_HOST_INFO;
         TransactionLegacy txn = TransactionLegacy.currentTxn();
-        ;
-        PreparedStatement pstmt = null;
-        try {
-            if (countAllPoolTypes) {
-                pstmt = txn.prepareAutoCloseStatement(STORAGE_POOL_HOST_INFO);
-            } else {
-                pstmt = txn.prepareAutoCloseStatement(SHARED_STORAGE_POOL_HOST_INFO);
-            }
+        try (PreparedStatement pstmt = txn.prepareAutoCloseStatement(sql)) {
             pstmt.setLong(1, dcId);
-
             ResultSet rs = pstmt.executeQuery();
             while (rs.next()) {
-                l.add(new Pair<Long, Integer>(rs.getLong(1), rs.getInt(2)));
+                poolCount = rs.getLong(1);
+                if (poolCount > 0) {
+                    return true;
+                }
             }
         } catch (SQLException e) {
             logger.debug("Caught SQLException: ", e);
         }
-        return l;
+        return false;
     }
 
     @Override
diff --git a/engine/schema/src/main/java/com/cloud/vm/dao/NicIpAliasDaoImpl.java b/engine/schema/src/main/java/com/cloud/vm/dao/NicIpAliasDaoImpl.java
index 887b3d73087e..44866c0a3585 100644
--- a/engine/schema/src/main/java/com/cloud/vm/dao/NicIpAliasDaoImpl.java
+++ b/engine/schema/src/main/java/com/cloud/vm/dao/NicIpAliasDaoImpl.java
@@ -170,8 +170,7 @@ public NicIpAliasVO findByIp4AddressAndNetworkIdAndInstanceId(long networkId, Lo
     public Integer countAliasIps(long id) {
         SearchCriteria<NicIpAliasVO> sc = AllFieldsSearch.create();
         sc.setParameters("instanceId", id);
-        List<NicIpAliasVO> list = listBy(sc);
-        return list.size();
+        return getCount(sc);
     }
 
     @Override
diff --git a/engine/schema/src/main/java/com/cloud/vm/dao/VMInstanceDao.java b/engine/schema/src/main/java/com/cloud/vm/dao/VMInstanceDao.java
index 52bc5aac7e25..4dee9130f513 100755
--- a/engine/schema/src/main/java/com/cloud/vm/dao/VMInstanceDao.java
+++ b/engine/schema/src/main/java/com/cloud/vm/dao/VMInstanceDao.java
@@ -16,6 +16,7 @@
 // under the License.
 package com.cloud.vm.dao;
 
+import java.util.Collection;
 import java.util.Date;
 import java.util.HashMap;
 import java.util.List;
@@ -81,7 +82,7 @@ public interface VMInstanceDao extends GenericDao<VMInstanceVO, Long>, StateDao<
 
     List<VMInstanceVO> listByHostAndState(long hostId, State... states);
 
-    List<VMInstanceVO> listByTypes(VirtualMachine.Type... types);
+    int countByTypes(VirtualMachine.Type... types);
 
     VMInstanceVO findByIdTypes(long id, VirtualMachine.Type... types);
 
@@ -144,21 +145,28 @@ public interface VMInstanceDao extends GenericDao<VMInstanceVO, Long>, StateDao<
      */
     List<String> listDistinctHostNames(long networkId, VirtualMachine.Type... types);
 
+    List<VMInstanceVO> findByHostInStatesExcluding(Long hostId, Collection<Long> excludingIds, State... states);
+
     List<VMInstanceVO> findByHostInStates(Long hostId, State... states);
 
     List<VMInstanceVO> listStartingWithNoHostId();
 
     boolean updatePowerState(long instanceId, long powerHostId, VirtualMachine.PowerState powerState, Date wisdomEra);
 
+    Map<Long, VirtualMachine.PowerState> updatePowerState(Map<Long, VirtualMachine.PowerState> instancePowerStates,
+              long powerHostId, Date wisdomEra);
+
     void resetVmPowerStateTracking(long instanceId);
 
+    void resetVmPowerStateTracking(List<Long> instanceId);
+
     void resetHostPowerStateTracking(long hostId);
 
     HashMap<String, Long> countVgpuVMs(Long dcId, Long podId, Long clusterId);
 
     VMInstanceVO findVMByHostNameInZone(String hostName, long zoneId);
 
-    boolean isPowerStateUpToDate(long instanceId);
+    boolean isPowerStateUpToDate(VMInstanceVO instance);
 
     List<VMInstanceVO> listNonMigratingVmsByHostEqualsLastHost(long hostId);
 
@@ -170,4 +178,15 @@ List<VMInstanceVO> searchRemovedByRemoveDate(final Date startDate, final Date en
              List<Long> skippedVmIds);
 
     Pair<List<VMInstanceVO>, Integer> listByVmsNotInClusterUsingPool(long clusterId, long poolId);
+
+    List<VMInstanceVO> listIdServiceOfferingForUpVmsByHostId(Long hostId);
+
+    List<VMInstanceVO> listIdServiceOfferingForVmsMigratingFromHost(Long hostId);
+
+    List<VMInstanceVO> listIdServiceOfferingForVmsByLastHostId(Long hostId);
+
+    Map<String, Long> getNameIdMapForVmInstanceNames(Collection<String> names);
+
+    Map<String, Long> getNameIdMapForVmIds(Collection<Long> ids);
+
 }
diff --git a/engine/schema/src/main/java/com/cloud/vm/dao/VMInstanceDaoImpl.java b/engine/schema/src/main/java/com/cloud/vm/dao/VMInstanceDaoImpl.java
index 744518ba7433..9df5795f69eb 100755
--- a/engine/schema/src/main/java/com/cloud/vm/dao/VMInstanceDaoImpl.java
+++ b/engine/schema/src/main/java/com/cloud/vm/dao/VMInstanceDaoImpl.java
@@ -20,6 +20,7 @@
 import java.sql.ResultSet;
 import java.sql.SQLException;
 import java.util.ArrayList;
+import java.util.Collection;
 import java.util.Date;
 import java.util.HashMap;
 import java.util.List;
@@ -75,6 +76,7 @@ public class VMInstanceDaoImpl extends GenericDaoBase<VMInstanceVO, Long> implem
     protected SearchBuilder<VMInstanceVO> LHVMClusterSearch;
     protected SearchBuilder<VMInstanceVO> IdStatesSearch;
     protected SearchBuilder<VMInstanceVO> AllFieldsSearch;
+    protected SearchBuilder<VMInstanceVO> IdServiceOfferingIdSelectSearch;
     protected SearchBuilder<VMInstanceVO> ZoneTemplateNonExpungedSearch;
     protected SearchBuilder<VMInstanceVO> TemplateNonExpungedSearch;
     protected SearchBuilder<VMInstanceVO> NameLikeSearch;
@@ -101,6 +103,7 @@ public class VMInstanceDaoImpl extends GenericDaoBase<VMInstanceVO, Long> implem
     protected SearchBuilder<VMInstanceVO> BackupSearch;
     protected SearchBuilder<VMInstanceVO> LastHostAndStatesSearch;
     protected SearchBuilder<VMInstanceVO> VmsNotInClusterUsingPool;
+    protected SearchBuilder<VMInstanceVO> IdsPowerStateSelectSearch;
 
     @Inject
     ResourceTagDao tagsDao;
@@ -177,6 +180,14 @@ protected void init() {
         AllFieldsSearch.and("account", AllFieldsSearch.entity().getAccountId(), Op.EQ);
         AllFieldsSearch.done();
 
+        IdServiceOfferingIdSelectSearch = createSearchBuilder();
+        IdServiceOfferingIdSelectSearch.and("host", IdServiceOfferingIdSelectSearch.entity().getHostId(), Op.EQ);
+        IdServiceOfferingIdSelectSearch.and("lastHost", IdServiceOfferingIdSelectSearch.entity().getLastHostId(), Op.EQ);
+        IdServiceOfferingIdSelectSearch.and("state", IdServiceOfferingIdSelectSearch.entity().getState(), Op.EQ);
+        IdServiceOfferingIdSelectSearch.and("states", IdServiceOfferingIdSelectSearch.entity().getState(), Op.IN);
+        IdServiceOfferingIdSelectSearch.selectFields(IdServiceOfferingIdSelectSearch.entity().getId(), IdServiceOfferingIdSelectSearch.entity().getServiceOfferingId());
+        IdServiceOfferingIdSelectSearch.done();
+
         ZoneTemplateNonExpungedSearch = createSearchBuilder();
         ZoneTemplateNonExpungedSearch.and("zone", ZoneTemplateNonExpungedSearch.entity().getDataCenterId(), Op.EQ);
         ZoneTemplateNonExpungedSearch.and("template", ZoneTemplateNonExpungedSearch.entity().getTemplateId(), Op.EQ);
@@ -276,6 +287,7 @@ protected void init() {
         HostAndStateSearch = createSearchBuilder();
         HostAndStateSearch.and("host", HostAndStateSearch.entity().getHostId(), Op.EQ);
         HostAndStateSearch.and("states", HostAndStateSearch.entity().getState(), Op.IN);
+        HostAndStateSearch.and("idsNotIn", HostAndStateSearch.entity().getId(), Op.NIN);
         HostAndStateSearch.done();
 
         StartingWithNoHostSearch = createSearchBuilder();
@@ -325,6 +337,15 @@ protected void init() {
         VmsNotInClusterUsingPool.join("hostSearch2", hostSearch2, hostSearch2.entity().getId(), VmsNotInClusterUsingPool.entity().getHostId(), JoinType.INNER);
         VmsNotInClusterUsingPool.and("vmStates", VmsNotInClusterUsingPool.entity().getState(), Op.IN);
         VmsNotInClusterUsingPool.done();
+
+        IdsPowerStateSelectSearch = createSearchBuilder();
+        IdsPowerStateSelectSearch.and("id", IdsPowerStateSelectSearch.entity().getId(), Op.IN);
+        IdsPowerStateSelectSearch.selectFields(IdsPowerStateSelectSearch.entity().getId(),
+                IdsPowerStateSelectSearch.entity().getPowerHostId(),
+                IdsPowerStateSelectSearch.entity().getPowerState(),
+                IdsPowerStateSelectSearch.entity().getPowerStateUpdateCount(),
+                IdsPowerStateSelectSearch.entity().getPowerStateUpdateTime());
+        IdsPowerStateSelectSearch.done();
     }
 
     @Override
@@ -460,10 +481,10 @@ public List<VMInstanceVO> listUpByHostId(Long hostId) {
     }
 
     @Override
-    public List<VMInstanceVO> listByTypes(Type... types) {
+    public int countByTypes(Type... types) {
         SearchCriteria<VMInstanceVO> sc = TypesSearch.create();
         sc.setParameters("types", (Object[])types);
-        return listBy(sc);
+        return getCount(sc);
     }
 
     @Override
@@ -899,6 +920,17 @@ public boolean remove(Long id) {
         return result;
     }
 
+    @Override
+    public List<VMInstanceVO> findByHostInStatesExcluding(Long hostId, Collection<Long> excludingIds, State... states) {
+        SearchCriteria<VMInstanceVO> sc = HostAndStateSearch.create();
+        sc.setParameters("host", hostId);
+        if (excludingIds != null && !excludingIds.isEmpty()) {
+            sc.setParameters("idsNotIn", excludingIds.toArray());
+        }
+        sc.setParameters("states", (Object[])states);
+        return listBy(sc);
+    }
+
     @Override
     public List<VMInstanceVO> findByHostInStates(Long hostId, State... states) {
         SearchCriteria<VMInstanceVO> sc = HostAndStateSearch.create();
@@ -914,40 +946,107 @@ public List<VMInstanceVO> listStartingWithNoHostId() {
         return listBy(sc);
     }
 
+    protected List<VMInstanceVO> listSelectPowerStateByIds(final List<Long> ids) {
+        if (CollectionUtils.isEmpty(ids)) {
+            return new ArrayList<>();
+        }
+        SearchCriteria<VMInstanceVO> sc = IdsPowerStateSelectSearch.create();
+        sc.setParameters("id", ids.toArray());
+        return customSearch(sc, null);
+    }
+
+    protected Integer getPowerUpdateCount(final VMInstanceVO instance, final long powerHostId,
+              final VirtualMachine.PowerState powerState, Date wisdomEra) {
+        if (instance.getPowerStateUpdateTime() == null || instance.getPowerStateUpdateTime().before(wisdomEra)) {
+            Long savedPowerHostId = instance.getPowerHostId();
+            boolean isStateMismatch = instance.getPowerState() != powerState
+                    || savedPowerHostId == null
+                    || !savedPowerHostId.equals(powerHostId)
+                    || !isPowerStateInSyncWithInstanceState(powerState, powerHostId, instance);
+            if (isStateMismatch) {
+                return 1;
+            } else if (instance.getPowerStateUpdateCount() < MAX_CONSECUTIVE_SAME_STATE_UPDATE_COUNT) {
+                return instance.getPowerStateUpdateCount() + 1;
+            }
+        }
+        return null;
+    }
+
     @Override
-    public boolean updatePowerState(final long instanceId, final long powerHostId, final VirtualMachine.PowerState powerState, Date wisdomEra) {
-        return Transaction.execute(new TransactionCallback<>() {
-            @Override
-            public Boolean doInTransaction(TransactionStatus status) {
-                boolean needToUpdate = false;
-                VMInstanceVO instance = findById(instanceId);
-                if (instance != null
-                        && (null == instance.getPowerStateUpdateTime()
-                        || instance.getPowerStateUpdateTime().before(wisdomEra))) {
-                    Long savedPowerHostId = instance.getPowerHostId();
-                    if (instance.getPowerState() != powerState
-                            || savedPowerHostId == null
-                            || savedPowerHostId != powerHostId
-                            || !isPowerStateInSyncWithInstanceState(powerState, powerHostId, instance)) {
-                        instance.setPowerState(powerState);
-                        instance.setPowerHostId(powerHostId);
-                        instance.setPowerStateUpdateCount(1);
-                        instance.setPowerStateUpdateTime(DateUtil.currentGMTTime());
-                        needToUpdate = true;
-                        update(instanceId, instance);
-                    } else {
-                        // to reduce DB updates, consecutive same state update for more than 3 times
-                        if (instance.getPowerStateUpdateCount() < MAX_CONSECUTIVE_SAME_STATE_UPDATE_COUNT) {
-                            instance.setPowerStateUpdateCount(instance.getPowerStateUpdateCount() + 1);
-                            instance.setPowerStateUpdateTime(DateUtil.currentGMTTime());
-                            needToUpdate = true;
-                            update(instanceId, instance);
-                        }
-                    }
+    public boolean updatePowerState(final long instanceId, final long powerHostId,
+            final VirtualMachine.PowerState powerState, Date wisdomEra) {
+        return Transaction.execute((TransactionCallback<Boolean>) status -> {
+            VMInstanceVO instance = findById(instanceId);
+            if (instance == null) {
+                return false;
+            }
+            // Check if we need to update based on powerStateUpdateTime
+            if (instance.getPowerStateUpdateTime() == null || instance.getPowerStateUpdateTime().before(wisdomEra)) {
+                Long savedPowerHostId = instance.getPowerHostId();
+                boolean isStateMismatch = instance.getPowerState() != powerState
+                        || savedPowerHostId == null
+                        || !savedPowerHostId.equals(powerHostId)
+                        || !isPowerStateInSyncWithInstanceState(powerState, powerHostId, instance);
+
+                if (isStateMismatch) {
+                    instance.setPowerState(powerState);
+                    instance.setPowerHostId(powerHostId);
+                    instance.setPowerStateUpdateCount(1);
+                } else if (instance.getPowerStateUpdateCount() < MAX_CONSECUTIVE_SAME_STATE_UPDATE_COUNT) {
+                    instance.setPowerStateUpdateCount(instance.getPowerStateUpdateCount() + 1);
+                } else {
+                    // No need to update if power state is already in sync and count exceeded
+                    return false;
                 }
-                return needToUpdate;
+                instance.setPowerStateUpdateTime(DateUtil.currentGMTTime());
+                update(instanceId, instance);
+                return true; // Return true since an update occurred
+            }
+            return false;
+        });
+    }
+
+    @Override
+    public Map<Long, VirtualMachine.PowerState> updatePowerState(
+            final Map<Long, VirtualMachine.PowerState> instancePowerStates, long powerHostId, Date wisdomEra) {
+        Map<Long, VirtualMachine.PowerState> notUpdated = new HashMap<>();
+        List<VMInstanceVO> instances = listSelectPowerStateByIds(new ArrayList<>(instancePowerStates.keySet()));
+        Map<Long, Integer> updateCounts = new HashMap<>();
+        for (VMInstanceVO instance : instances) {
+            VirtualMachine.PowerState powerState = instancePowerStates.get(instance.getId());
+            Integer count = getPowerUpdateCount(instance, powerHostId, powerState, wisdomEra);
+            if (count != null) {
+                updateCounts.put(instance.getId(), count);
+            } else {
+                notUpdated.put(instance.getId(), powerState);
             }
+        }
+        if (updateCounts.isEmpty()) {
+            return notUpdated;
+        }
+        StringBuilder sql = new StringBuilder("UPDATE `cloud`.`vm_instance` SET " +
+                "`power_host` = ?, `power_state_update_time` = now(), `power_state` = CASE ");
+        updateCounts.keySet().forEach(key -> {
+            sql.append("WHEN id = ").append(key).append(" THEN '").append(instancePowerStates.get(key)).append("' ");
+        });
+        sql.append("END, `power_state_update_count` = CASE ");
+        StringBuilder idList = new StringBuilder();
+        updateCounts.forEach((key, value) -> {
+            sql.append("WHEN `id` = ").append(key).append(" THEN ").append(value).append(" ");
+            idList.append(key).append(",");
         });
+        idList.setLength(idList.length() - 1);
+        sql.append("END WHERE `id` IN (").append(idList).append(")");
+        TransactionLegacy txn = TransactionLegacy.currentTxn();
+        try (PreparedStatement pstmt = txn.prepareAutoCloseStatement(sql.toString())) {
+            pstmt.setLong(1, powerHostId);
+            pstmt.executeUpdate();
+        } catch (SQLException e) {
+            logger.error(String.format("Unable to execute update power states SQL from VMs %s due to: %s",
+                    idList, e.getMessage()), e);
+            return instancePowerStates;
+        }
+        return notUpdated;
     }
 
     private boolean isPowerStateInSyncWithInstanceState(final VirtualMachine.PowerState powerState, final long powerHostId, final VMInstanceVO instance) {
@@ -962,11 +1061,7 @@ private boolean isPowerStateInSyncWithInstanceState(final VirtualMachine.PowerSt
     }
 
     @Override
-    public boolean isPowerStateUpToDate(final long instanceId) {
-        VMInstanceVO instance = findById(instanceId);
-        if(instance == null) {
-            throw new CloudRuntimeException("checking power state update count on non existing instance " + instanceId);
-        }
+    public boolean isPowerStateUpToDate(final VMInstanceVO instance) {
         return instance.getPowerStateUpdateCount() < MAX_CONSECUTIVE_SAME_STATE_UPDATE_COUNT;
     }
 
@@ -985,6 +1080,22 @@ public void doInTransactionWithoutResult(TransactionStatus status) {
         });
     }
 
+    @Override
+    public void resetVmPowerStateTracking(List<Long> instanceIds) {
+        Transaction.execute(new TransactionCallbackNoReturn() {
+            @Override
+            public void doInTransactionWithoutResult(TransactionStatus status) {
+                SearchCriteria<VMInstanceVO> sc = IdsPowerStateSelectSearch.create();
+                sc.setParameters("id", instanceIds.toArray());
+                VMInstanceVO vm = createForUpdate();
+                vm.setPowerStateUpdateCount(0);
+                vm.setPowerStateUpdateTime(DateUtil.currentGMTTime());
+                UpdateBuilder ub = getUpdateBuilder(vm);
+                update(ub, sc, null);
+            }
+        });
+    }
+
     @Override @DB
     public void resetHostPowerStateTracking(final long hostId) {
         Transaction.execute(new TransactionCallbackNoReturn() {
@@ -1060,6 +1171,7 @@ public List<VMInstanceVO> searchRemovedByRemoveDate(Date startDate, Date endDate
         return searchIncludingRemoved(sc, filter, null, false);
     }
 
+    @Override
     public Pair<List<VMInstanceVO>, Integer> listByVmsNotInClusterUsingPool(long clusterId, long poolId) {
         SearchCriteria<VMInstanceVO> sc = VmsNotInClusterUsingPool.create();
         sc.setParameters("vmStates", State.Starting, State.Running, State.Stopping, State.Migrating, State.Restoring);
@@ -1069,4 +1181,52 @@ public Pair<List<VMInstanceVO>, Integer> listByVmsNotInClusterUsingPool(long clu
         List<VMInstanceVO> uniqueVms = vms.stream().distinct().collect(Collectors.toList());
         return new Pair<>(uniqueVms, uniqueVms.size());
     }
+
+    @Override
+    public List<VMInstanceVO> listIdServiceOfferingForUpVmsByHostId(Long hostId) {
+        SearchCriteria<VMInstanceVO> sc = IdServiceOfferingIdSelectSearch.create();
+        sc.setParameters("host", hostId);
+        sc.setParameters("states", new Object[] {State.Starting, State.Running, State.Stopping, State.Migrating});
+        return customSearch(sc, null);
+    }
+
+    @Override
+    public List<VMInstanceVO> listIdServiceOfferingForVmsMigratingFromHost(Long hostId) {
+        SearchCriteria<VMInstanceVO> sc = IdServiceOfferingIdSelectSearch.create();
+        sc.setParameters("lastHost", hostId);
+        sc.setParameters("state", State.Migrating);
+        return customSearch(sc, null);
+    }
+
+    @Override
+    public List<VMInstanceVO> listIdServiceOfferingForVmsByLastHostId(Long hostId) {
+        SearchCriteria<VMInstanceVO> sc = IdServiceOfferingIdSelectSearch.create();
+        sc.setParameters("lastHost", hostId);
+        sc.setParameters("state", State.Stopped);
+        return customSearch(sc, null);
+    }
+
+    @Override
+    public Map<String, Long> getNameIdMapForVmInstanceNames(Collection<String> names) {
+        SearchBuilder<VMInstanceVO> sb = createSearchBuilder();
+        sb.and("name", sb.entity().getInstanceName(), Op.IN);
+        sb.selectFields(sb.entity().getId(), sb.entity().getInstanceName());
+        SearchCriteria<VMInstanceVO> sc = sb.create();
+        sc.setParameters("name", names.toArray());
+        List<VMInstanceVO> vms = customSearch(sc, null);
+        return vms.stream()
+                .collect(Collectors.toMap(VMInstanceVO::getInstanceName, VMInstanceVO::getId));
+    }
+
+    @Override
+    public Map<String, Long> getNameIdMapForVmIds(Collection<Long> ids) {
+        SearchBuilder<VMInstanceVO> sb = createSearchBuilder();
+        sb.and("id", sb.entity().getId(), Op.IN);
+        sb.selectFields(sb.entity().getId(), sb.entity().getInstanceName());
+        SearchCriteria<VMInstanceVO> sc = sb.create();
+        sc.setParameters("id", ids.toArray());
+        List<VMInstanceVO> vms = customSearch(sc, null);
+        return vms.stream()
+                .collect(Collectors.toMap(VMInstanceVO::getInstanceName, VMInstanceVO::getId));
+    }
 }
diff --git a/engine/schema/src/main/java/org/apache/cloudstack/resourcedetail/ResourceDetailsDao.java b/engine/schema/src/main/java/org/apache/cloudstack/resourcedetail/ResourceDetailsDao.java
index 8f3d264da981..6d0d9378c7c5 100644
--- a/engine/schema/src/main/java/org/apache/cloudstack/resourcedetail/ResourceDetailsDao.java
+++ b/engine/schema/src/main/java/org/apache/cloudstack/resourcedetail/ResourceDetailsDao.java
@@ -88,6 +88,8 @@ public interface ResourceDetailsDao<R extends ResourceDetail> extends GenericDao
 
     public Map<String, String> listDetailsKeyPairs(long resourceId);
 
+    Map<String, String> listDetailsKeyPairs(long resourceId, List<String> keys);
+
     public Map<String, String> listDetailsKeyPairs(long resourceId, boolean forDisplay);
 
     Map<String, Boolean> listDetailsVisibility(long resourceId);
diff --git a/engine/schema/src/main/java/org/apache/cloudstack/resourcedetail/ResourceDetailsDaoBase.java b/engine/schema/src/main/java/org/apache/cloudstack/resourcedetail/ResourceDetailsDaoBase.java
index 4205a7823e44..f2e156f225ae 100644
--- a/engine/schema/src/main/java/org/apache/cloudstack/resourcedetail/ResourceDetailsDaoBase.java
+++ b/engine/schema/src/main/java/org/apache/cloudstack/resourcedetail/ResourceDetailsDaoBase.java
@@ -19,6 +19,7 @@
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.stream.Collectors;
 
 import org.apache.cloudstack.api.ResourceDetail;
 import org.apache.commons.collections.CollectionUtils;
@@ -91,6 +92,20 @@ public Map<String, String> listDetailsKeyPairs(long resourceId) {
         return details;
     }
 
+    @Override
+    public Map<String, String> listDetailsKeyPairs(long resourceId, List<String> keys) {
+        SearchBuilder<R> sb = createSearchBuilder();
+        sb.and("resourceId", sb.entity().getResourceId(), SearchCriteria.Op.EQ);
+        sb.and("name", sb.entity().getName(), SearchCriteria.Op.IN);
+        sb.done();
+        SearchCriteria<R> sc = sb.create();
+        sc.setParameters("resourceId", resourceId);
+        sc.setParameters("name", keys.toArray());
+
+        List<R> results = search(sc, null);
+        return results.stream().collect(Collectors.toMap(R::getName, R::getValue));
+    }
+
     public Map<String, Boolean> listDetailsVisibility(long resourceId) {
         SearchCriteria<R> sc = AllFieldsSearch.create();
         sc.setParameters("resourceId", resourceId);
diff --git a/engine/schema/src/main/java/org/apache/cloudstack/storage/datastore/db/PrimaryDataStoreDao.java b/engine/schema/src/main/java/org/apache/cloudstack/storage/datastore/db/PrimaryDataStoreDao.java
index f0c235e842c1..7c97d8009b4a 100644
--- a/engine/schema/src/main/java/org/apache/cloudstack/storage/datastore/db/PrimaryDataStoreDao.java
+++ b/engine/schema/src/main/java/org/apache/cloudstack/storage/datastore/db/PrimaryDataStoreDao.java
@@ -154,4 +154,6 @@ Pair<List<Long>, Integer> searchForIdsAndCount(Long storagePoolId, String storag
             String keyword, Filter searchFilter);
 
     List<StoragePoolVO> listByIds(List<Long> ids);
+
+    List<Long> listAllIds();
 }
diff --git a/engine/schema/src/main/java/org/apache/cloudstack/storage/datastore/db/PrimaryDataStoreDaoImpl.java b/engine/schema/src/main/java/org/apache/cloudstack/storage/datastore/db/PrimaryDataStoreDaoImpl.java
index 1658fe0a537e..ae12573e36e9 100644
--- a/engine/schema/src/main/java/org/apache/cloudstack/storage/datastore/db/PrimaryDataStoreDaoImpl.java
+++ b/engine/schema/src/main/java/org/apache/cloudstack/storage/datastore/db/PrimaryDataStoreDaoImpl.java
@@ -28,20 +28,20 @@
 import javax.inject.Inject;
 import javax.naming.ConfigurationException;
 
-import com.cloud.storage.Storage;
-import com.cloud.utils.Pair;
-import com.cloud.utils.db.Filter;
 import org.apache.commons.collections.CollectionUtils;
 
 import com.cloud.host.Status;
 import com.cloud.hypervisor.Hypervisor.HypervisorType;
 import com.cloud.storage.ScopeType;
+import com.cloud.storage.Storage;
 import com.cloud.storage.StoragePoolHostVO;
 import com.cloud.storage.StoragePoolStatus;
 import com.cloud.storage.StoragePoolTagVO;
 import com.cloud.storage.dao.StoragePoolHostDao;
 import com.cloud.storage.dao.StoragePoolTagsDao;
+import com.cloud.utils.Pair;
 import com.cloud.utils.db.DB;
+import com.cloud.utils.db.Filter;
 import com.cloud.utils.db.GenericDaoBase;
 import com.cloud.utils.db.GenericSearchBuilder;
 import com.cloud.utils.db.JoinBuilder;
@@ -800,4 +800,12 @@ private SearchCriteria<StoragePoolVO> createStoragePoolSearchCriteria(Long stora
         sc.setParameters("parent", 0);
         return sc;
     }
+
+    @Override
+    public List<Long> listAllIds() {
+        GenericSearchBuilder<StoragePoolVO, Long> sb = createSearchBuilder(Long.class);
+        sb.selectFields(sb.entity().getId());
+        sb.done();
+        return customSearch(sb.create(), null);
+    }
 }
diff --git a/engine/schema/src/main/resources/META-INF/db/views/cloud.network_offering_view.sql b/engine/schema/src/main/resources/META-INF/db/views/cloud.network_offering_view.sql
index b6abaabcd48f..640b2397a461 100644
--- a/engine/schema/src/main/resources/META-INF/db/views/cloud.network_offering_view.sql
+++ b/engine/schema/src/main/resources/META-INF/db/views/cloud.network_offering_view.sql
@@ -76,13 +76,9 @@ SELECT
 FROM
     `cloud`.`network_offerings`
         LEFT JOIN
-    `cloud`.`network_offering_details` AS `domain_details` ON `domain_details`.`network_offering_id` = `network_offerings`.`id` AND `domain_details`.`name`='domainid'
+    `cloud`.`domain` AS `domain` ON `domain`.id IN (SELECT value from `network_offering_details` where `name` = 'domainid' and `network_offering_id` = `network_offerings`.`id`)
         LEFT JOIN
-    `cloud`.`domain` AS `domain` ON FIND_IN_SET(`domain`.`id`, `domain_details`.`value`)
-        LEFT JOIN
-    `cloud`.`network_offering_details` AS `zone_details` ON `zone_details`.`network_offering_id` = `network_offerings`.`id` AND `zone_details`.`name`='zoneid'
-        LEFT JOIN
-    `cloud`.`data_center` AS `zone` ON FIND_IN_SET(`zone`.`id`, `zone_details`.`value`)
+    `cloud`.`data_center` AS `zone` ON `zone`.`id` IN (SELECT value from `network_offering_details` where `name` = 'zoneid' and `network_offering_id` = `network_offerings`.`id`)
         LEFT JOIN
     `cloud`.`network_offering_details` AS `offering_details` ON `offering_details`.`network_offering_id` = `network_offerings`.`id` AND `offering_details`.`name`='internetProtocol'
 GROUP BY
diff --git a/engine/schema/src/test/java/com/cloud/usage/dao/UsageStorageDaoImplTest.java b/engine/schema/src/test/java/com/cloud/usage/dao/UsageStorageDaoImplTest.java
index 05d9154b6a45..fa47d2cd90b4 100644
--- a/engine/schema/src/test/java/com/cloud/usage/dao/UsageStorageDaoImplTest.java
+++ b/engine/schema/src/test/java/com/cloud/usage/dao/UsageStorageDaoImplTest.java
@@ -23,12 +23,9 @@
 import static org.mockito.Mockito.when;
 
 import java.sql.PreparedStatement;
-import com.cloud.utils.DateUtil;
-import com.cloud.utils.db.TransactionLegacy;
 import java.util.Date;
 import java.util.TimeZone;
 
-import com.cloud.usage.UsageStorageVO;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.mockito.Mock;
@@ -36,6 +33,10 @@
 import org.mockito.Mockito;
 import org.mockito.junit.MockitoJUnitRunner;
 
+import com.cloud.usage.UsageStorageVO;
+import com.cloud.utils.DateUtil;
+import com.cloud.utils.db.TransactionLegacy;
+
 @RunWith(MockitoJUnitRunner.class)
 public class UsageStorageDaoImplTest {
 
diff --git a/framework/agent-lb/src/main/java/org/apache/cloudstack/agent/lb/IndirectAgentLBAlgorithm.java b/framework/agent-lb/src/main/java/org/apache/cloudstack/agent/lb/IndirectAgentLBAlgorithm.java
index c87a0996fcc9..062d2226876f 100644
--- a/framework/agent-lb/src/main/java/org/apache/cloudstack/agent/lb/IndirectAgentLBAlgorithm.java
+++ b/framework/agent-lb/src/main/java/org/apache/cloudstack/agent/lb/IndirectAgentLBAlgorithm.java
@@ -42,4 +42,8 @@ public interface IndirectAgentLBAlgorithm {
      * @return true if the lists are equal, false if not
      */
     boolean compare(final List<String> msList, final List<String> receivedMsList);
+
+    default boolean isHostListNeeded() {
+        return false;
+    }
 }
diff --git a/framework/cluster/src/main/java/com/cloud/cluster/dao/ManagementServerHostPeerDaoImpl.java b/framework/cluster/src/main/java/com/cloud/cluster/dao/ManagementServerHostPeerDaoImpl.java
index 827be4fe2998..c7fad068d490 100644
--- a/framework/cluster/src/main/java/com/cloud/cluster/dao/ManagementServerHostPeerDaoImpl.java
+++ b/framework/cluster/src/main/java/com/cloud/cluster/dao/ManagementServerHostPeerDaoImpl.java
@@ -96,7 +96,6 @@ public int countStateSeenInPeers(long mshost, long runid, ManagementServerHost.S
         sc.setParameters("peerRunid", runid);
         sc.setParameters("peerState", state);
 
-        List<ManagementServerHostPeerVO> l = listBy(sc);
-        return l.size();
+        return getCount(sc);
     }
 }
diff --git a/framework/config/src/main/java/org/apache/cloudstack/framework/config/impl/ConfigDepotImpl.java b/framework/config/src/main/java/org/apache/cloudstack/framework/config/impl/ConfigDepotImpl.java
index b47370d92059..911a4ad37078 100644
--- a/framework/config/src/main/java/org/apache/cloudstack/framework/config/impl/ConfigDepotImpl.java
+++ b/framework/config/src/main/java/org/apache/cloudstack/framework/config/impl/ConfigDepotImpl.java
@@ -23,7 +23,6 @@
 import java.util.HashSet;
 import java.util.List;
 import java.util.Set;
-import java.util.concurrent.TimeUnit;
 
 import javax.annotation.PostConstruct;
 import javax.inject.Inject;
@@ -36,6 +35,7 @@
 import org.apache.cloudstack.framework.config.dao.ConfigurationDao;
 import org.apache.cloudstack.framework.config.dao.ConfigurationGroupDao;
 import org.apache.cloudstack.framework.config.dao.ConfigurationSubGroupDao;
+import org.apache.cloudstack.utils.cache.LazyCache;
 import org.apache.commons.lang.ObjectUtils;
 import org.apache.commons.lang3.StringUtils;
 import org.apache.logging.log4j.LogManager;
@@ -44,8 +44,6 @@
 import com.cloud.utils.Pair;
 import com.cloud.utils.Ternary;
 import com.cloud.utils.exception.CloudRuntimeException;
-import com.github.benmanes.caffeine.cache.Cache;
-import com.github.benmanes.caffeine.cache.Caffeine;
 
 /**
  * ConfigDepotImpl implements the ConfigDepot and ConfigDepotAdmin interface.
@@ -87,17 +85,15 @@ public class ConfigDepotImpl implements ConfigDepot, ConfigDepotAdmin {
     List<ScopedConfigStorage> _scopedStorages;
     Set<Configurable> _configured = Collections.synchronizedSet(new HashSet<Configurable>());
     Set<String> newConfigs = Collections.synchronizedSet(new HashSet<>());
-    Cache<String, String> configCache;
+    LazyCache<String, String> configCache;
 
     private HashMap<String, Pair<String, ConfigKey<?>>> _allKeys = new HashMap<String, Pair<String, ConfigKey<?>>>(1007);
 
     HashMap<ConfigKey.Scope, Set<ConfigKey<?>>> _scopeLevelConfigsMap = new HashMap<ConfigKey.Scope, Set<ConfigKey<?>>>();
 
     public ConfigDepotImpl() {
-        configCache = Caffeine.newBuilder()
-                .maximumSize(512)
-                .expireAfterWrite(CONFIG_CACHE_EXPIRE_SECONDS, TimeUnit.SECONDS)
-                .build();
+        configCache = new LazyCache<>(512,
+                CONFIG_CACHE_EXPIRE_SECONDS, this::getConfigStringValueInternal);
         ConfigKey.init(this);
         createEmptyScopeLevelMappings();
     }
@@ -311,7 +307,7 @@ private String getConfigCacheKey(String key, ConfigKey.Scope scope, Long scopeId
 
     @Override
     public String getConfigStringValue(String key, ConfigKey.Scope scope, Long scopeId) {
-        return configCache.get(getConfigCacheKey(key, scope, scopeId), this::getConfigStringValueInternal);
+        return configCache.get(getConfigCacheKey(key, scope, scopeId));
     }
 
     @Override
diff --git a/framework/db/src/main/java/com/cloud/utils/db/GenericDaoBase.java b/framework/db/src/main/java/com/cloud/utils/db/GenericDaoBase.java
index 82fea9749ff8..e2295cadd3b7 100644
--- a/framework/db/src/main/java/com/cloud/utils/db/GenericDaoBase.java
+++ b/framework/db/src/main/java/com/cloud/utils/db/GenericDaoBase.java
@@ -2441,4 +2441,11 @@ private Optional<AttributeConverter<Object, Object>> getConverter(Field field) {
         }
     }
 
+    public static class SumCount {
+        public long sum;
+        public long count;
+
+        public SumCount() {
+        }
+    }
 }
diff --git a/framework/db/src/main/java/com/cloud/utils/db/TransactionLegacy.java b/framework/db/src/main/java/com/cloud/utils/db/TransactionLegacy.java
index 88af397c06a9..10b82052eedb 100644
--- a/framework/db/src/main/java/com/cloud/utils/db/TransactionLegacy.java
+++ b/framework/db/src/main/java/com/cloud/utils/db/TransactionLegacy.java
@@ -1334,7 +1334,7 @@ private static DataSource createDbcpDataSource(String uri, String username, Stri
             poolableConnectionFactory.setDefaultTransactionIsolation(isolationLevel);
         }
         return new PoolingDataSource<>(connectionPool);
-    }
+     }
 
     /**
      * Return a GenericObjectPoolConfig configuration usable on connection pool creation
diff --git a/framework/jobs/src/main/java/org/apache/cloudstack/framework/jobs/dao/VmWorkJobDao.java b/framework/jobs/src/main/java/org/apache/cloudstack/framework/jobs/dao/VmWorkJobDao.java
index b3bfda0334cf..79ec3f2b0872 100644
--- a/framework/jobs/src/main/java/org/apache/cloudstack/framework/jobs/dao/VmWorkJobDao.java
+++ b/framework/jobs/src/main/java/org/apache/cloudstack/framework/jobs/dao/VmWorkJobDao.java
@@ -40,4 +40,5 @@ public interface VmWorkJobDao extends GenericDao<VmWorkJobVO, Long> {
 
     void expungeLeftoverWorkJobs(long msid);
     int expungeByVmList(List<Long> vmIds, Long batchSize);
+    List<Long> listVmIdsWithPendingJob();
 }
diff --git a/framework/jobs/src/main/java/org/apache/cloudstack/framework/jobs/dao/VmWorkJobDaoImpl.java b/framework/jobs/src/main/java/org/apache/cloudstack/framework/jobs/dao/VmWorkJobDaoImpl.java
index 3b167498a377..a467b5fdf59e 100644
--- a/framework/jobs/src/main/java/org/apache/cloudstack/framework/jobs/dao/VmWorkJobDaoImpl.java
+++ b/framework/jobs/src/main/java/org/apache/cloudstack/framework/jobs/dao/VmWorkJobDaoImpl.java
@@ -24,6 +24,7 @@
 import javax.annotation.PostConstruct;
 import javax.inject.Inject;
 
+import org.apache.cloudstack.framework.jobs.impl.AsyncJobVO;
 import org.apache.cloudstack.framework.jobs.impl.VmWorkJobVO;
 import org.apache.cloudstack.framework.jobs.impl.VmWorkJobVO.Step;
 import org.apache.cloudstack.jobs.JobInfo;
@@ -32,6 +33,8 @@
 import com.cloud.utils.DateUtil;
 import com.cloud.utils.db.Filter;
 import com.cloud.utils.db.GenericDaoBase;
+import com.cloud.utils.db.GenericSearchBuilder;
+import com.cloud.utils.db.JoinBuilder;
 import com.cloud.utils.db.SearchBuilder;
 import com.cloud.utils.db.SearchCriteria;
 import com.cloud.utils.db.SearchCriteria.Op;
@@ -224,4 +227,17 @@ public int expungeByVmList(List<Long> vmIds, Long batchSize) {
         sc.setParameters("vmIds", vmIds.toArray());
         return batchExpunge(sc, batchSize);
     }
+
+    @Override
+    public List<Long> listVmIdsWithPendingJob() {
+        GenericSearchBuilder<VmWorkJobVO, Long> sb = createSearchBuilder(Long.class);
+        SearchBuilder<AsyncJobVO> asyncJobSearch = _baseJobDao.createSearchBuilder();
+        asyncJobSearch.and("status", asyncJobSearch.entity().getStatus(), SearchCriteria.Op.EQ);
+        sb.join("asyncJobSearch", asyncJobSearch, sb.entity().getId(), asyncJobSearch.entity().getId(), JoinBuilder.JoinType.INNER);
+        sb.and("removed", sb.entity().getRemoved(), Op.NULL);
+        sb.selectFields(sb.entity().getVmInstanceId());
+        SearchCriteria<Long> sc = sb.create();
+        sc.setJoinParameters("asyncJobSearch", "status", JobInfo.Status.IN_PROGRESS);
+        return customSearch(sc, null);
+    }
 }
diff --git a/plugins/acl/dynamic-role-based/src/main/java/org/apache/cloudstack/acl/DynamicRoleBasedAPIAccessChecker.java b/plugins/acl/dynamic-role-based/src/main/java/org/apache/cloudstack/acl/DynamicRoleBasedAPIAccessChecker.java
index db40b6e68ddd..030e0bcf0141 100644
--- a/plugins/acl/dynamic-role-based/src/main/java/org/apache/cloudstack/acl/DynamicRoleBasedAPIAccessChecker.java
+++ b/plugins/acl/dynamic-role-based/src/main/java/org/apache/cloudstack/acl/DynamicRoleBasedAPIAccessChecker.java
@@ -26,20 +26,21 @@
 import javax.inject.Inject;
 import javax.naming.ConfigurationException;
 
-import org.apache.cloudstack.api.APICommand;
 import org.apache.cloudstack.acl.RolePermissionEntity.Permission;
+import org.apache.cloudstack.api.APICommand;
+import org.apache.cloudstack.utils.cache.LazyCache;
+import org.apache.commons.lang3.StringUtils;
 
 import com.cloud.exception.PermissionDeniedException;
 import com.cloud.exception.UnavailableCommandException;
 import com.cloud.user.Account;
 import com.cloud.user.AccountService;
 import com.cloud.user.User;
+import com.cloud.utils.Pair;
 import com.cloud.utils.component.AdapterBase;
 import com.cloud.utils.component.PluggableService;
-import org.apache.commons.lang3.StringUtils;
 
 public class DynamicRoleBasedAPIAccessChecker extends AdapterBase implements APIAclChecker {
-
     @Inject
     private AccountService accountService;
     @Inject
@@ -48,6 +49,9 @@ public class DynamicRoleBasedAPIAccessChecker extends AdapterBase implements API
     private List<PluggableService> services;
     private Map<RoleType, Set<String>> annotationRoleBasedApisMap = new HashMap<RoleType, Set<String>>();
 
+    private LazyCache<Long, Account> accountCache;
+    private LazyCache<Long, Pair<Role, List<RolePermission>>> rolePermissionsCache;
+    private int cachePeriod;
 
     protected DynamicRoleBasedAPIAccessChecker() {
         super();
@@ -99,23 +103,66 @@ public boolean checkApiPermissionByRole(Role role, String apiName, List<RolePerm
                 annotationRoleBasedApisMap.get(role.getRoleType()).contains(apiName);
     }
 
+    protected Account getAccountFromId(long accountId) {
+        return accountService.getAccount(accountId);
+    }
+
+    protected Pair<Role, List<RolePermission>> getRolePermissions(long roleId) {
+        final Role accountRole = roleService.findRole(roleId);
+        if (accountRole == null || accountRole.getId() < 1L) {
+            return new Pair<>(null, null);
+        }
+
+        if (accountRole.getRoleType() == RoleType.Admin && accountRole.getId() == RoleType.Admin.getId()) {
+            return new Pair<>(accountRole, null);
+        }
+
+        return new Pair<>(accountRole, roleService.findAllPermissionsBy(accountRole.getId()));
+    }
+
+    protected Pair<Role, List<RolePermission>> getRolePermissionsUsingCache(long roleId) {
+        if (cachePeriod > 0) {
+            return rolePermissionsCache.get(roleId);
+        }
+        return getRolePermissions(roleId);
+    }
+
+    protected Account getAccountFromIdUsingCache(long accountId) {
+        if (cachePeriod > 0) {
+            return accountCache.get(accountId);
+        }
+        return getAccountFromId(accountId);
+    }
+
     @Override
     public boolean checkAccess(User user, String commandName) throws PermissionDeniedException {
         if (!isEnabled()) {
             return true;
         }
-
-        Account account = accountService.getAccount(user.getAccountId());
+        Account account = getAccountFromIdUsingCache(user.getAccountId());
         if (account == null) {
-            throw new PermissionDeniedException(String.format("The account id [%s] for user id [%s] is null.", user.getAccountId(), user.getUuid()));
+            throw new PermissionDeniedException(String.format("Account for user id [%s] cannot be found", user.getUuid()));
         }
-
-        return checkAccess(account, commandName);
+        Pair<Role, List<RolePermission>> roleAndPermissions = getRolePermissionsUsingCache(account.getRoleId());
+        final Role accountRole = roleAndPermissions.first();
+        if (accountRole == null) {
+            throw new PermissionDeniedException(String.format("Account role for user id [%s] cannot be found.", user.getUuid()));
+        }
+        if (accountRole.getRoleType() == RoleType.Admin && accountRole.getId() == RoleType.Admin.getId()) {
+            logger.info("Account for user id {} is Root Admin or Domain Admin, all APIs are allowed.", user.getUuid());
+            return true;
+        }
+        List<RolePermission> allPermissions = roleAndPermissions.second();
+        if (checkApiPermissionByRole(accountRole, commandName, allPermissions)) {
+            return true;
+        }
+        throw new UnavailableCommandException(String.format("The API [%s] does not exist or is not available for the account for user id [%s].", commandName, user.getUuid()));
     }
 
     public boolean checkAccess(Account account, String commandName) {
-        final Role accountRole = roleService.findRole(account.getRoleId());
-        if (accountRole == null || accountRole.getId() < 1L) {
+        Pair<Role, List<RolePermission>> roleAndPermissions = getRolePermissionsUsingCache(account.getRoleId());
+        final Role accountRole = roleAndPermissions.first();
+        if (accountRole == null) {
             throw new PermissionDeniedException(String.format("The account [%s] has role null or unknown.", account));
         }
 
@@ -160,6 +207,9 @@ public void addApiToRoleBasedAnnotationsMap(final RoleType roleType, final Strin
     @Override
     public boolean configure(String name, Map<String, Object> params) throws ConfigurationException {
         super.configure(name, params);
+        cachePeriod = Math.max(0, RoleService.DynamicApiCheckerCachePeriod.value());
+        accountCache = new LazyCache<>(32, cachePeriod, this::getAccountFromId);
+        rolePermissionsCache = new LazyCache<>(32, cachePeriod, this::getRolePermissions);
         return true;
     }
 
diff --git a/plugins/affinity-group-processors/explicit-dedication/src/main/java/org/apache/cloudstack/affinity/ExplicitDedicationProcessor.java b/plugins/affinity-group-processors/explicit-dedication/src/main/java/org/apache/cloudstack/affinity/ExplicitDedicationProcessor.java
index ec6674477b07..342ac4568f2f 100644
--- a/plugins/affinity-group-processors/explicit-dedication/src/main/java/org/apache/cloudstack/affinity/ExplicitDedicationProcessor.java
+++ b/plugins/affinity-group-processors/explicit-dedication/src/main/java/org/apache/cloudstack/affinity/ExplicitDedicationProcessor.java
@@ -321,13 +321,13 @@ private ExcludeList updateAvoidList(List<DedicatedResourceVO> dedicatedResources
                     }
                 }
                 //add all hosts inside this in includeList
-                List<HostVO> hostList = _hostDao.listByDataCenterId(dr.getDataCenterId());
-                for (HostVO host : hostList) {
-                    DedicatedResourceVO dHost = _dedicatedDao.findByHostId(host.getId());
+                List<Long> hostList = _hostDao.listEnabledIdsByDataCenterId(dr.getDataCenterId());
+                for (Long hostId : hostList) {
+                    DedicatedResourceVO dHost = _dedicatedDao.findByHostId(hostId);
                     if (dHost != null && !dedicatedResources.contains(dHost)) {
-                        avoidList.addHost(host.getId());
+                        avoidList.addHost(hostId);
                     } else {
-                        includeList.addHost(host.getId());
+                        includeList.addHost(hostId);
                     }
                 }
             }
@@ -337,7 +337,7 @@ private ExcludeList updateAvoidList(List<DedicatedResourceVO> dedicatedResources
 
         List<HostPodVO> pods = _podDao.listByDataCenterId(dc.getId());
         List<ClusterVO> clusters = _clusterDao.listClustersByDcId(dc.getId());
-        List<HostVO> hosts = _hostDao.listByDataCenterId(dc.getId());
+        List<Long> hostIds = _hostDao.listEnabledIdsByDataCenterId(dc.getId());
         Set<Long> podsInIncludeList = includeList.getPodsToAvoid();
         Set<Long> clustersInIncludeList = includeList.getClustersToAvoid();
         Set<Long> hostsInIncludeList = includeList.getHostsToAvoid();
@@ -357,9 +357,9 @@ private ExcludeList updateAvoidList(List<DedicatedResourceVO> dedicatedResources
             }
         }
 
-        for (HostVO host : hosts) {
-            if (hostsInIncludeList != null && !hostsInIncludeList.contains(host.getId())) {
-                avoidList.addHost(host.getId());
+        for (Long hostId : hostIds) {
+            if (hostsInIncludeList != null && !hostsInIncludeList.contains(hostId)) {
+                avoidList.addHost(hostId);
             }
         }
         return avoidList;
diff --git a/plugins/dedicated-resources/src/main/java/org/apache/cloudstack/dedicated/DedicatedResourceManagerImpl.java b/plugins/dedicated-resources/src/main/java/org/apache/cloudstack/dedicated/DedicatedResourceManagerImpl.java
index 4f1db396b7c4..7633a895ecd6 100644
--- a/plugins/dedicated-resources/src/main/java/org/apache/cloudstack/dedicated/DedicatedResourceManagerImpl.java
+++ b/plugins/dedicated-resources/src/main/java/org/apache/cloudstack/dedicated/DedicatedResourceManagerImpl.java
@@ -23,7 +23,6 @@
 import javax.inject.Inject;
 import javax.naming.ConfigurationException;
 
-import org.apache.commons.lang3.StringUtils;
 import org.apache.cloudstack.affinity.AffinityGroup;
 import org.apache.cloudstack.affinity.AffinityGroupService;
 import org.apache.cloudstack.affinity.dao.AffinityGroupDao;
@@ -45,8 +44,9 @@
 import org.apache.cloudstack.api.response.DedicateZoneResponse;
 import org.apache.cloudstack.context.CallContext;
 import org.apache.cloudstack.framework.config.dao.ConfigurationDao;
-import org.apache.logging.log4j.Logger;
+import org.apache.commons.lang3.StringUtils;
 import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
 import org.springframework.stereotype.Component;
 
 import com.cloud.configuration.Config;
@@ -126,7 +126,7 @@ public boolean configure(final String name, final Map<String, Object> params) th
     @ActionEvent(eventType = EventTypes.EVENT_DEDICATE_RESOURCE, eventDescription = "dedicating a Zone")
     public List<DedicatedResourceVO> dedicateZone(final Long zoneId, final Long domainId, final String accountName) {
         Long accountId = null;
-        List<HostVO> hosts = null;
+        List<Long> hostIds = null;
         if (accountName != null) {
             Account caller = CallContext.current().getCallingAccount();
             Account owner = _accountMgr.finalizeOwner(caller, accountName, domainId, null);
@@ -203,18 +203,20 @@ public List<DedicatedResourceVO> dedicateZone(final Long zoneId, final Long doma
                 releaseDedicatedResource(null, null, dr.getClusterId(), null);
             }
 
-            hosts = _hostDao.listByDataCenterId(dc.getId());
-            for (HostVO host : hosts) {
-                DedicatedResourceVO dHost = _dedicatedDao.findByHostId(host.getId());
+            hostIds = _hostDao.listEnabledIdsByDataCenterId(dc.getId());
+            for (Long hostId : hostIds) {
+                DedicatedResourceVO dHost = _dedicatedDao.findByHostId(hostId);
                 if (dHost != null) {
                     if (!(childDomainIds.contains(dHost.getDomainId()))) {
+                        HostVO host = _hostDao.findById(hostId);
                         throw new CloudRuntimeException("Host " + host.getName() + " under this Zone " + dc.getName() + " is dedicated to different account/domain");
                     }
                     if (accountId != null) {
                         if (dHost.getAccountId().equals(accountId)) {
                             hostsToRelease.add(dHost);
                         } else {
-                            logger.error("Host " + host.getName() + " under this Zone " + dc.getName() + " is dedicated to different account/domain");
+                            HostVO host = _hostDao.findById(hostId);
+                            logger.error("Host {} under this Zone {} is dedicated to different account/domain", host.getName(), dc.getName());
                             throw new CloudRuntimeException("Host " + host.getName() + " under this Zone " + dc.getName() + " is dedicated to different account/domain");
                         }
                     } else {
@@ -230,7 +232,7 @@ public List<DedicatedResourceVO> dedicateZone(final Long zoneId, final Long doma
             }
         }
 
-        checkHostsSuitabilityForExplicitDedication(accountId, childDomainIds, hosts);
+        checkHostsSuitabilityForExplicitDedication(accountId, childDomainIds, hostIds);
 
         final Long accountIdFinal = accountId;
         return Transaction.execute(new TransactionCallback<List<DedicatedResourceVO>>() {
@@ -284,7 +286,7 @@ public List<DedicatedResourceVO> dedicatePod(final Long podId, final Long domain
         childDomainIds.add(domainId);
         checkAccountAndDomain(accountId, domainId);
         HostPodVO pod = _podDao.findById(podId);
-        List<HostVO> hosts = null;
+        List<Long> hostIds = null;
         if (pod == null) {
             throw new InvalidParameterValueException("Unable to find pod by id " + podId);
         } else {
@@ -339,18 +341,20 @@ public List<DedicatedResourceVO> dedicatePod(final Long podId, final Long domain
                 releaseDedicatedResource(null, null, dr.getClusterId(), null);
             }
 
-            hosts = _hostDao.findByPodId(pod.getId());
-            for (HostVO host : hosts) {
-                DedicatedResourceVO dHost = _dedicatedDao.findByHostId(host.getId());
+            hostIds = _hostDao.listIdsByPodId(pod.getId());
+            for (Long hostId : hostIds) {
+                DedicatedResourceVO dHost = _dedicatedDao.findByHostId(hostId);
                 if (dHost != null) {
                     if (!(getDomainChildIds(domainId).contains(dHost.getDomainId()))) {
+                        HostVO host = _hostDao.findById(hostId);
                         throw new CloudRuntimeException("Host " + host.getName() + " under this Pod " + pod.getName() + " is dedicated to different account/domain");
                     }
                     if (accountId != null) {
                         if (dHost.getAccountId().equals(accountId)) {
                             hostsToRelease.add(dHost);
                         } else {
-                            logger.error("Host " + host.getName() + " under this Pod " + pod.getName() + " is dedicated to different account/domain");
+                            HostVO host = _hostDao.findById(hostId);
+                            logger.error("Host {} under this Pod {} is dedicated to different account/domain", host.getName(), pod.getName());
                             throw new CloudRuntimeException("Host " + host.getName() + " under this Pod " + pod.getName() + " is dedicated to different account/domain");
                         }
                     } else {
@@ -366,7 +370,7 @@ public List<DedicatedResourceVO> dedicatePod(final Long podId, final Long domain
             }
         }
 
-        checkHostsSuitabilityForExplicitDedication(accountId, childDomainIds, hosts);
+        checkHostsSuitabilityForExplicitDedication(accountId, childDomainIds, hostIds);
 
         final Long accountIdFinal = accountId;
         return Transaction.execute(new TransactionCallback<List<DedicatedResourceVO>>() {
@@ -402,7 +406,7 @@ public List<DedicatedResourceVO> doInTransaction(TransactionStatus status) {
     @ActionEvent(eventType = EventTypes.EVENT_DEDICATE_RESOURCE, eventDescription = "dedicating a Cluster")
     public List<DedicatedResourceVO> dedicateCluster(final Long clusterId, final Long domainId, final String accountName) {
         Long accountId = null;
-        List<HostVO> hosts = null;
+        List<Long> hostIds = null;
         if (accountName != null) {
             Account caller = CallContext.current().getCallingAccount();
             Account owner = _accountMgr.finalizeOwner(caller, accountName, domainId, null);
@@ -448,12 +452,13 @@ public List<DedicatedResourceVO> dedicateCluster(final Long clusterId, final Lon
             }
 
             //check if any resource under this cluster is dedicated to different account or sub-domain
-            hosts = _hostDao.findByClusterId(cluster.getId());
+            hostIds = _hostDao.listIdsByClusterId(cluster.getId());
             List<DedicatedResourceVO> hostsToRelease = new ArrayList<DedicatedResourceVO>();
-            for (HostVO host : hosts) {
-                DedicatedResourceVO dHost = _dedicatedDao.findByHostId(host.getId());
+            for (Long hostId : hostIds) {
+                DedicatedResourceVO dHost = _dedicatedDao.findByHostId(hostId);
                 if (dHost != null) {
                     if (!(childDomainIds.contains(dHost.getDomainId()))) {
+                        HostVO host = _hostDao.findById(hostId);
                         throw new CloudRuntimeException("Host " + host.getName() + " under this Cluster " + cluster.getName() +
                             " is dedicated to different account/domain");
                     }
@@ -479,7 +484,7 @@ public List<DedicatedResourceVO> dedicateCluster(final Long clusterId, final Lon
             }
         }
 
-        checkHostsSuitabilityForExplicitDedication(accountId, childDomainIds, hosts);
+        checkHostsSuitabilityForExplicitDedication(accountId, childDomainIds, hostIds);
 
         final Long accountIdFinal = accountId;
         return Transaction.execute(new TransactionCallback<List<DedicatedResourceVO>>() {
@@ -685,10 +690,10 @@ private boolean checkHostSuitabilityForExplicitDedication(Long accountId, List<L
         return suitable;
     }
 
-    private boolean checkHostsSuitabilityForExplicitDedication(Long accountId, List<Long> domainIds, List<HostVO> hosts) {
+    private boolean checkHostsSuitabilityForExplicitDedication(Long accountId, List<Long> domainIds, List<Long> hostIds) {
         boolean suitable = true;
-        for (HostVO host : hosts) {
-            checkHostSuitabilityForExplicitDedication(accountId, domainIds, host.getId());
+        for (Long hostId : hostIds) {
+            checkHostSuitabilityForExplicitDedication(accountId, domainIds, hostId);
         }
         return suitable;
     }
diff --git a/plugins/deployment-planners/implicit-dedication/src/main/java/com/cloud/deploy/ImplicitDedicationPlanner.java b/plugins/deployment-planners/implicit-dedication/src/main/java/com/cloud/deploy/ImplicitDedicationPlanner.java
index bd1bcf061013..5bbdd3411b42 100644
--- a/plugins/deployment-planners/implicit-dedication/src/main/java/com/cloud/deploy/ImplicitDedicationPlanner.java
+++ b/plugins/deployment-planners/implicit-dedication/src/main/java/com/cloud/deploy/ImplicitDedicationPlanner.java
@@ -21,14 +21,15 @@
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
+import java.util.stream.Collectors;
 
 import javax.inject.Inject;
 import javax.naming.ConfigurationException;
 
+import org.apache.commons.collections.CollectionUtils;
 
 import com.cloud.configuration.Config;
 import com.cloud.exception.InsufficientServerCapacityException;
-import com.cloud.host.HostVO;
 import com.cloud.resource.ResourceManager;
 import com.cloud.service.ServiceOfferingVO;
 import com.cloud.service.dao.ServiceOfferingDao;
@@ -38,7 +39,6 @@
 import com.cloud.utils.NumbersUtil;
 import com.cloud.vm.VMInstanceVO;
 import com.cloud.vm.VirtualMachineProfile;
-import org.springframework.util.CollectionUtils;
 
 public class ImplicitDedicationPlanner extends FirstFitPlanner implements DeploymentClusterPlanner {
 
@@ -73,12 +73,11 @@ public List<Long> orderClusters(VirtualMachineProfile vmProfile, DeploymentPlan
         boolean preferred = isServiceOfferingUsingPlannerInPreferredMode(vmProfile.getServiceOfferingId());
 
         // Get the list of all the hosts in the given clusters
-        List<Long> allHosts = new ArrayList<Long>();
-        for (Long cluster : clusterList) {
-            List<HostVO> hostsInCluster = resourceMgr.listAllHostsInCluster(cluster);
-            for (HostVO hostVO : hostsInCluster) {
-                allHosts.add(hostVO.getId());
-            }
+        List<Long> allHosts = new ArrayList<>();
+        if (CollectionUtils.isNotEmpty(clusterList)) {
+            allHosts = clusterList.stream()
+                    .flatMap(cluster -> hostDao.listIdsByClusterId(cluster).stream())
+                    .collect(Collectors.toList());
         }
 
         // Go over all the hosts in the cluster and get a list of
@@ -221,20 +220,15 @@ private boolean isServiceOfferingUsingPlannerInPreferredMode(long serviceOfferin
     }
 
     private List<Long> getUpdatedClusterList(List<Long> clusterList, Set<Long> hostsSet) {
-        List<Long> updatedClusterList = new ArrayList<Long>();
-        for (Long cluster : clusterList) {
-            List<HostVO> hosts = resourceMgr.listAllHostsInCluster(cluster);
-            Set<Long> hostsInClusterSet = new HashSet<Long>();
-            for (HostVO host : hosts) {
-                hostsInClusterSet.add(host.getId());
-            }
-
-            if (!hostsSet.containsAll(hostsInClusterSet)) {
-                updatedClusterList.add(cluster);
-            }
+        if (CollectionUtils.isEmpty(clusterList)) {
+            return new ArrayList<>();
         }
-
-        return updatedClusterList;
+        return clusterList.stream()
+                .filter(cluster -> {
+                    Set<Long> hostsInClusterSet = new HashSet<>(hostDao.listIdsByClusterId(cluster));
+                    return !hostsSet.containsAll(hostsInClusterSet);
+                })
+                .collect(Collectors.toList());
     }
 
     @Override
@@ -254,15 +248,11 @@ public PlannerResourceUsage getResourceUsage(VirtualMachineProfile vmProfile, De
             Account account = vmProfile.getOwner();
 
             // Get the list of all the hosts in the given clusters
-            List<Long> allHosts = new ArrayList<Long>();
-            if (!CollectionUtils.isEmpty(clusterList)) {
-                for (Long cluster : clusterList) {
-                    List<HostVO> hostsInCluster = resourceMgr.listAllHostsInCluster(cluster);
-                    for (HostVO hostVO : hostsInCluster) {
-
-                        allHosts.add(hostVO.getId());
-                    }
-                }
+            List<Long> allHosts = new ArrayList<>();
+            if (CollectionUtils.isNotEmpty(clusterList)) {
+                allHosts = clusterList.stream()
+                        .flatMap(cluster -> hostDao.listIdsByClusterId(cluster).stream())
+                        .collect(Collectors.toList());
             }
             // Go over all the hosts in the cluster and get a list of
             // 1. All empty hosts, not running any vms.
diff --git a/plugins/deployment-planners/implicit-dedication/src/test/java/org/apache/cloudstack/implicitplanner/ImplicitPlannerTest.java b/plugins/deployment-planners/implicit-dedication/src/test/java/org/apache/cloudstack/implicitplanner/ImplicitPlannerTest.java
index e174824cfdd2..2d2b4c78261e 100644
--- a/plugins/deployment-planners/implicit-dedication/src/test/java/org/apache/cloudstack/implicitplanner/ImplicitPlannerTest.java
+++ b/plugins/deployment-planners/implicit-dedication/src/test/java/org/apache/cloudstack/implicitplanner/ImplicitPlannerTest.java
@@ -16,11 +16,11 @@
 // under the License.
 package org.apache.cloudstack.implicitplanner;
 
-import static org.junit.Assert.assertFalse;
-import static org.junit.Assert.assertTrue;
 import static org.hamcrest.MatcherAssert.assertThat;
-import static org.hamcrest.Matchers.everyItem;
 import static org.hamcrest.Matchers.equalTo;
+import static org.hamcrest.Matchers.everyItem;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
 import static org.mockito.ArgumentMatchers.anyString;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.when;
@@ -36,7 +36,11 @@
 
 import javax.inject.Inject;
 
-import com.cloud.user.User;
+import org.apache.cloudstack.context.CallContext;
+import org.apache.cloudstack.engine.subsystem.api.storage.DataStoreManager;
+import org.apache.cloudstack.framework.config.dao.ConfigurationDao;
+import org.apache.cloudstack.storage.datastore.db.PrimaryDataStoreDao;
+import org.apache.cloudstack.test.utils.SpringUtils;
 import org.junit.After;
 import org.junit.Before;
 import org.junit.Test;
@@ -54,12 +58,6 @@
 import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
 import org.springframework.test.context.support.AnnotationConfigContextLoader;
 
-import org.apache.cloudstack.context.CallContext;
-import org.apache.cloudstack.engine.subsystem.api.storage.DataStoreManager;
-import org.apache.cloudstack.framework.config.dao.ConfigurationDao;
-import org.apache.cloudstack.storage.datastore.db.PrimaryDataStoreDao;
-import org.apache.cloudstack.test.utils.SpringUtils;
-
 import com.cloud.capacity.Capacity;
 import com.cloud.capacity.CapacityManager;
 import com.cloud.capacity.dao.CapacityDao;
@@ -73,7 +71,6 @@
 import com.cloud.deploy.ImplicitDedicationPlanner;
 import com.cloud.exception.InsufficientServerCapacityException;
 import com.cloud.gpu.dao.HostGpuGroupsDao;
-import com.cloud.host.HostVO;
 import com.cloud.host.dao.HostDao;
 import com.cloud.host.dao.HostDetailsDao;
 import com.cloud.host.dao.HostTagsDao;
@@ -90,6 +87,7 @@
 import com.cloud.user.Account;
 import com.cloud.user.AccountManager;
 import com.cloud.user.AccountVO;
+import com.cloud.user.User;
 import com.cloud.user.UserVO;
 import com.cloud.utils.Pair;
 import com.cloud.utils.component.ComponentContext;
@@ -387,21 +385,9 @@ private void initializeForImplicitPlannerTest(boolean preferred) {
         when(serviceOfferingDetailsDao.listDetailsKeyPairs(offeringId)).thenReturn(details);
 
         // Initialize hosts in clusters
-        HostVO host1 = mock(HostVO.class);
-        when(host1.getId()).thenReturn(5L);
-        HostVO host2 = mock(HostVO.class);
-        when(host2.getId()).thenReturn(6L);
-        HostVO host3 = mock(HostVO.class);
-        when(host3.getId()).thenReturn(7L);
-        List<HostVO> hostsInCluster1 = new ArrayList<HostVO>();
-        List<HostVO> hostsInCluster2 = new ArrayList<HostVO>();
-        List<HostVO> hostsInCluster3 = new ArrayList<HostVO>();
-        hostsInCluster1.add(host1);
-        hostsInCluster2.add(host2);
-        hostsInCluster3.add(host3);
-        when(resourceMgr.listAllHostsInCluster(1)).thenReturn(hostsInCluster1);
-        when(resourceMgr.listAllHostsInCluster(2)).thenReturn(hostsInCluster2);
-        when(resourceMgr.listAllHostsInCluster(3)).thenReturn(hostsInCluster3);
+        when(hostDao.listIdsByClusterId(1L)).thenReturn(List.of(5L));
+        when(hostDao.listIdsByClusterId(2L)).thenReturn(List.of(6L));
+        when(hostDao.listIdsByClusterId(3L)).thenReturn(List.of(7L));
 
         // Mock vms on each host.
         long offeringIdForVmsOfThisAccount = 15L;
diff --git a/plugins/hypervisors/simulator/src/main/java/com/cloud/resource/AgentRoutingResource.java b/plugins/hypervisors/simulator/src/main/java/com/cloud/resource/AgentRoutingResource.java
index 80ced4c230db..570b8008f95b 100644
--- a/plugins/hypervisors/simulator/src/main/java/com/cloud/resource/AgentRoutingResource.java
+++ b/plugins/hypervisors/simulator/src/main/java/com/cloud/resource/AgentRoutingResource.java
@@ -109,7 +109,8 @@ public Type getType() {
     public PingCommand getCurrentStatus(long id) {
         TransactionLegacy txn = TransactionLegacy.open(TransactionLegacy.SIMULATOR_DB);
         try {
-            MockConfigurationVO config = _simMgr.getMockConfigurationDao().findByNameBottomUP(agentHost.getDataCenterId(), agentHost.getPodId(), agentHost.getClusterId(), agentHost.getId(), "PingCommand");
+            //MockConfigurationVO config = _simMgr.getMockConfigurationDao().findByNameBottomUP(agentHost.getDataCenterId(), agentHost.getPodId(), agentHost.getClusterId(), agentHost.getId(), "PingCommand");
+            MockConfigurationVO config = null;
             if (config != null) {
                 Map<String, String> configParameters = config.getParameters();
                 for (Map.Entry<String, String> entry : configParameters.entrySet()) {
@@ -122,7 +123,8 @@ public PingCommand getCurrentStatus(long id) {
                 }
             }
 
-            config = _simMgr.getMockConfigurationDao().findByNameBottomUP(agentHost.getDataCenterId(), agentHost.getPodId(), agentHost.getClusterId(), agentHost.getId(), "PingRoutingWithNwGroupsCommand");
+            //config = _simMgr.getMockConfigurationDao().findByNameBottomUP(agentHost.getDataCenterId(), agentHost.getPodId(), agentHost.getClusterId(), agentHost.getId(), "PingRoutingWithNwGroupsCommand");
+            config = null;
             if (config != null) {
                 String message = config.getJsonResponse();
                 if (message != null) {
diff --git a/plugins/hypervisors/xenserver/src/main/java/com/cloud/hypervisor/xenserver/discoverer/XcpServerDiscoverer.java b/plugins/hypervisors/xenserver/src/main/java/com/cloud/hypervisor/xenserver/discoverer/XcpServerDiscoverer.java
index 8a5e59e4373c..4fa7e7882244 100644
--- a/plugins/hypervisors/xenserver/src/main/java/com/cloud/hypervisor/xenserver/discoverer/XcpServerDiscoverer.java
+++ b/plugins/hypervisors/xenserver/src/main/java/com/cloud/hypervisor/xenserver/discoverer/XcpServerDiscoverer.java
@@ -31,6 +31,7 @@
 import javax.persistence.EntityExistsException;
 
 import org.apache.cloudstack.hypervisor.xenserver.XenserverConfigs;
+import org.apache.commons.collections.CollectionUtils;
 import org.apache.commons.lang3.StringUtils;
 import org.apache.maven.artifact.versioning.ComparableVersion;
 import org.apache.xmlrpc.XmlRpcException;
@@ -144,8 +145,8 @@ void setClusterGuid(ClusterVO cluster, String guid) {
             sc.and(sc.entity().getGuid(), Op.EQ, guid);
             List<ClusterVO> clusters = sc.list();
             ClusterVO clu = clusters.get(0);
-            List<HostVO> clusterHosts = _resourceMgr.listAllHostsInCluster(clu.getId());
-            if (clusterHosts == null || clusterHosts.size() == 0) {
+            List<Long> clusterHostIds = _hostDao.listIdsByClusterId(clu.getId());
+            if (CollectionUtils.isEmpty(clusterHostIds)) {
                 clu.setGuid(null);
                 _clusterDao.update(clu.getId(), clu);
                 _clusterDao.update(cluster.getId(), cluster);
@@ -245,8 +246,8 @@ protected boolean poolHasHotFix(Connection conn, String hostIp, String hotFixUui
             if (clu.getGuid() == null) {
                 setClusterGuid(clu, poolUuid);
             } else {
-                List<HostVO> clusterHosts = _resourceMgr.listAllHostsInCluster(clusterId);
-                if (clusterHosts != null && clusterHosts.size() > 0) {
+                List<Long> clusterHostIds = _hostDao.listIdsByClusterId(clusterId);
+                if (CollectionUtils.isNotEmpty(clusterHostIds)) {
                     if (!clu.getGuid().equals(poolUuid)) {
                         String msg = "Please join the host " +  hostIp + " to XS pool  "
                                 + clu.getGuid() + " through XC/XS before adding it through CS UI";
diff --git a/plugins/integrations/prometheus/src/main/java/org/apache/cloudstack/metrics/PrometheusExporterImpl.java b/plugins/integrations/prometheus/src/main/java/org/apache/cloudstack/metrics/PrometheusExporterImpl.java
index a84b1a6e2dea..e5dc0b291713 100644
--- a/plugins/integrations/prometheus/src/main/java/org/apache/cloudstack/metrics/PrometheusExporterImpl.java
+++ b/plugins/integrations/prometheus/src/main/java/org/apache/cloudstack/metrics/PrometheusExporterImpl.java
@@ -298,8 +298,8 @@ private void addHostTagsMetrics(final List<Item> metricsList, final long dcId, f
                     metricsList.add(new ItemHostMemory(zoneName, zoneUuid, null, null, null, null, ALLOCATED, allocatedCapacityByTag.third(), 0, tag));
                 });
 
-        List<HostTagVO> allHostTagVOS = hostDao.listAll().stream()
-                .flatMap( h -> _hostTagsDao.getHostTags(h.getId()).stream())
+        List<HostTagVO> allHostTagVOS = hostDao.listAllIds().stream()
+                .flatMap( h -> _hostTagsDao.getHostTags(h).stream())
                 .distinct()
                 .collect(Collectors.toList());
         List<String> allHostTags = new ArrayList<>();
diff --git a/plugins/metrics/src/main/java/org/apache/cloudstack/metrics/MetricsService.java b/plugins/metrics/src/main/java/org/apache/cloudstack/metrics/MetricsService.java
index 48033dd75389..bb7763688385 100644
--- a/plugins/metrics/src/main/java/org/apache/cloudstack/metrics/MetricsService.java
+++ b/plugins/metrics/src/main/java/org/apache/cloudstack/metrics/MetricsService.java
@@ -30,6 +30,7 @@
 import org.apache.cloudstack.api.response.UserVmResponse;
 import org.apache.cloudstack.api.response.VolumeResponse;
 import org.apache.cloudstack.api.response.ZoneResponse;
+import org.apache.cloudstack.framework.config.ConfigKey;
 import org.apache.cloudstack.response.ClusterMetricsResponse;
 import org.apache.cloudstack.response.DbMetricsResponse;
 import org.apache.cloudstack.response.HostMetricsResponse;
@@ -47,6 +48,11 @@
 import com.cloud.utils.component.PluggableService;
 
 public interface MetricsService extends PluggableService {
+
+    ConfigKey<Boolean> AllowListMetricsComputation = new ConfigKey<>("Advanced", Boolean.class, "allow.list.metrics.computation", "true",
+            "Whether the list zones and cluster metrics APIs are allowed metrics computation. Large environments may disabled this.",
+            true, ConfigKey.Scope.Global);
+
     InfrastructureResponse listInfrastructure();
 
     ListResponse<VmMetricsStatsResponse> searchForVmMetricsStats(ListVMsUsageHistoryCmd cmd);
@@ -56,10 +62,10 @@ public interface MetricsService extends PluggableService {
     List<VmMetricsResponse> listVmMetrics(List<UserVmResponse> vmResponses);
     List<StoragePoolMetricsResponse> listStoragePoolMetrics(List<StoragePoolResponse> poolResponses);
     List<HostMetricsResponse> listHostMetrics(List<HostResponse> poolResponses);
-    List<ManagementServerMetricsResponse> listManagementServerMetrics(List<ManagementServerResponse> poolResponses);
     List<ClusterMetricsResponse> listClusterMetrics(Pair<List<ClusterResponse>, Integer> clusterResponses);
     List<ZoneMetricsResponse> listZoneMetrics(List<ZoneResponse> poolResponses);
 
+    List<ManagementServerMetricsResponse> listManagementServerMetrics(List<ManagementServerResponse> poolResponses);
     UsageServerMetricsResponse listUsageServerMetrics();
     DbMetricsResponse listDbMetrics();
 }
diff --git a/plugins/metrics/src/main/java/org/apache/cloudstack/metrics/MetricsServiceImpl.java b/plugins/metrics/src/main/java/org/apache/cloudstack/metrics/MetricsServiceImpl.java
index 6025a41d69cb..64ceddcc1a0c 100644
--- a/plugins/metrics/src/main/java/org/apache/cloudstack/metrics/MetricsServiceImpl.java
+++ b/plugins/metrics/src/main/java/org/apache/cloudstack/metrics/MetricsServiceImpl.java
@@ -61,6 +61,8 @@
 import org.apache.cloudstack.api.response.ZoneResponse;
 import org.apache.cloudstack.cluster.ClusterDrsAlgorithm;
 import org.apache.cloudstack.context.CallContext;
+import org.apache.cloudstack.framework.config.ConfigKey;
+import org.apache.cloudstack.framework.config.Configurable;
 import org.apache.cloudstack.management.ManagementServerHost.State;
 import org.apache.cloudstack.response.ClusterMetricsResponse;
 import org.apache.cloudstack.response.DbMetricsResponse;
@@ -110,8 +112,6 @@
 import com.cloud.host.dao.HostDao;
 import com.cloud.network.router.VirtualRouter;
 import com.cloud.org.Cluster;
-import com.cloud.org.Grouping;
-import com.cloud.org.Managed;
 import com.cloud.server.DbStatsCollection;
 import com.cloud.server.ManagementServerHostStats;
 import com.cloud.server.StatsCollector;
@@ -141,8 +141,7 @@
 import com.cloud.vm.dao.VmStatsDao;
 import com.google.gson.Gson;
 
-public class MetricsServiceImpl extends MutualExclusiveIdsManagerBase implements MetricsService {
-
+public class MetricsServiceImpl extends MutualExclusiveIdsManagerBase implements MetricsService, Configurable {
     @Inject
     private DataCenterDao dataCenterDao;
     @Inject
@@ -197,7 +196,6 @@ private Double findRatioValue(final String value) {
     }
 
     private void updateHostMetrics(final HostMetrics hostMetrics, final HostJoinVO host) {
-        hostMetrics.incrTotalHosts();
         hostMetrics.addCpuAllocated(host.getCpuReservedCapacity() + host.getCpuUsedCapacity());
         hostMetrics.addMemoryAllocated(host.getMemReservedCapacity() + host.getMemUsedCapacity());
         final HostStats hostStats = ApiDBUtils.getHostStatistics(host.getId());
@@ -561,22 +559,17 @@ public InfrastructureResponse listInfrastructure() {
         response.setZones(dataCenterDao.countAll());
         response.setPods(podDao.countAll());
         response.setClusters(clusterDao.countAll());
-        response.setHosts(hostDao.countAllByType(Host.Type.Routing));
+        Pair<Integer, Integer> hostCountAndCpuSockets = hostDao.countAllHostsAndCPUSocketsByType(Host.Type.Routing);
+        response.setHosts(hostCountAndCpuSockets.first());
         response.setStoragePools(storagePoolDao.countAll());
         response.setImageStores(imageStoreDao.countAllImageStores());
         response.setObjectStores(objectStoreDao.countAllObjectStores());
-        response.setSystemvms(vmInstanceDao.listByTypes(VirtualMachine.Type.ConsoleProxy, VirtualMachine.Type.SecondaryStorageVm).size());
+        response.setSystemvms(vmInstanceDao.countByTypes(VirtualMachine.Type.ConsoleProxy, VirtualMachine.Type.SecondaryStorageVm));
         response.setRouters(domainRouterDao.countAllByRole(VirtualRouter.Role.VIRTUAL_ROUTER));
         response.setInternalLbs(domainRouterDao.countAllByRole(VirtualRouter.Role.INTERNAL_LB_VM));
         response.setAlerts(alertDao.countAll());
-        int cpuSockets = 0;
-        for (final Host host : hostDao.listByType(Host.Type.Routing)) {
-            if (host.getCpuSockets() != null) {
-                cpuSockets += host.getCpuSockets();
-            }
-        }
-        response.setCpuSockets(cpuSockets);
-        response.setManagementServers(managementServerHostDao.listAll().size());
+        response.setCpuSockets(hostCountAndCpuSockets.second());
+        response.setManagementServers(managementServerHostDao.countAll());
         return response;
     }
 
@@ -764,38 +757,44 @@ public List<ClusterMetricsResponse> listClusterMetrics(Pair<List<ClusterResponse
             final CapacityDaoImpl.SummedCapacity cpuCapacity = getCapacity(Capacity.CAPACITY_TYPE_CPU, null, clusterId);
             final CapacityDaoImpl.SummedCapacity memoryCapacity = getCapacity(Capacity.CAPACITY_TYPE_MEMORY, null, clusterId);
             final HostMetrics hostMetrics = new HostMetrics(cpuCapacity, memoryCapacity);
-
-            List<Ternary<Long, Long, Long>> cpuList = new ArrayList<>();
-            List<Ternary<Long, Long, Long>> memoryList = new ArrayList<>();
-
-            for (final Host host: hostDao.findByClusterId(clusterId)) {
-                if (host == null || host.getType() != Host.Type.Routing) {
-                    continue;
+            hostMetrics.setUpResources(Long.valueOf(hostDao.countAllInClusterByTypeAndStates(clusterId, Host.Type.Routing, List.of(Status.Up))));
+            hostMetrics.setTotalResources(Long.valueOf(hostDao.countAllInClusterByTypeAndStates(clusterId, Host.Type.Routing, null)));
+            hostMetrics.setTotalHosts(hostMetrics.getTotalResources());
+
+            if (AllowListMetricsComputation.value()) {
+                List<Ternary<Long, Long, Long>> cpuList = new ArrayList<>();
+                List<Ternary<Long, Long, Long>> memoryList = new ArrayList<>();
+                for (final Host host : hostDao.findByClusterId(clusterId)) {
+                    if (host == null || host.getType() != Host.Type.Routing) {
+                        continue;
+                    }
+                    updateHostMetrics(hostMetrics, hostJoinDao.findById(host.getId()));
+                    HostJoinVO hostJoin = hostJoinDao.findById(host.getId());
+                    cpuList.add(new Ternary<>(hostJoin.getCpuUsedCapacity(), hostJoin.getCpuReservedCapacity(), hostJoin.getCpus() * hostJoin.getSpeed()));
+                    memoryList.add(new Ternary<>(hostJoin.getMemUsedCapacity(), hostJoin.getMemReservedCapacity(), hostJoin.getTotalMemory()));
                 }
-                if (host.getStatus() == Status.Up) {
-                    hostMetrics.incrUpResources();
+                try {
+                    Double imbalance = ClusterDrsAlgorithm.getClusterImbalance(clusterId, cpuList, memoryList, null);
+                    metricsResponse.setDrsImbalance(imbalance.isNaN() ? null : 100.0 * imbalance);
+                } catch (ConfigurationException e) {
+                    logger.warn("Failed to get cluster imbalance for cluster {}", clusterId, e);
+                }
+            } else {
+                if (cpuCapacity != null) {
+                    hostMetrics.setCpuAllocated(cpuCapacity.getAllocatedCapacity());
+                }
+                if (memoryCapacity != null) {
+                    hostMetrics.setMemoryAllocated(memoryCapacity.getAllocatedCapacity());
                 }
-                hostMetrics.incrTotalResources();
-                HostJoinVO hostJoin = hostJoinDao.findById(host.getId());
-                updateHostMetrics(hostMetrics, hostJoin);
-
-                cpuList.add(new Ternary<>(hostJoin.getCpuUsedCapacity(), hostJoin.getCpuReservedCapacity(), hostJoin.getCpus() * hostJoin.getSpeed()));
-                memoryList.add(new Ternary<>(hostJoin.getMemUsedCapacity(), hostJoin.getMemReservedCapacity(), hostJoin.getTotalMemory()));
-            }
-
-            try {
-                Double imbalance = ClusterDrsAlgorithm.getClusterImbalance(clusterId, cpuList, memoryList, null);
-                metricsResponse.setDrsImbalance(imbalance.isNaN() ? null : 100.0 * imbalance);
-            } catch (ConfigurationException e) {
-                logger.warn("Failed to get cluster imbalance for cluster " + clusterId, e);
             }
 
-            metricsResponse.setState(clusterResponse.getAllocationState(), clusterResponse.getManagedState());
-            metricsResponse.setResources(hostMetrics.getUpResources(), hostMetrics.getTotalResources());
             addHostCpuMetricsToResponse(metricsResponse, clusterId, hostMetrics);
             addHostMemoryMetricsToResponse(metricsResponse, clusterId, hostMetrics);
 
             metricsResponse.setHasAnnotation(clusterResponse.hasAnnotation());
+            metricsResponse.setState(clusterResponse.getAllocationState(), clusterResponse.getManagedState());
+            metricsResponse.setResources(hostMetrics.getUpResources(), hostMetrics.getTotalResources());
+
             metricsResponses.add(metricsResponse);
         }
         return metricsResponses;
@@ -942,35 +941,38 @@ public List<ZoneMetricsResponse> listZoneMetrics(List<ZoneResponse> zoneResponse
             final CapacityDaoImpl.SummedCapacity cpuCapacity = getCapacity((int) Capacity.CAPACITY_TYPE_CPU, zoneId, null);
             final CapacityDaoImpl.SummedCapacity memoryCapacity = getCapacity((int) Capacity.CAPACITY_TYPE_MEMORY, zoneId, null);
             final HostMetrics hostMetrics = new HostMetrics(cpuCapacity, memoryCapacity);
+            hostMetrics.setUpResources(Long.valueOf(clusterDao.countAllManagedAndEnabledByDcId(zoneId)));
+            hostMetrics.setTotalResources(Long.valueOf(clusterDao.countAllByDcId(zoneId)));
+            hostMetrics.setTotalHosts(Long.valueOf(hostDao.countAllByTypeInZone(zoneId, Host.Type.Routing)));
 
-            for (final Cluster cluster : clusterDao.listClustersByDcId(zoneId)) {
-                if (cluster == null) {
-                    continue;
-                }
-                hostMetrics.incrTotalResources();
-                if (cluster.getAllocationState() == Grouping.AllocationState.Enabled
-                        && cluster.getManagedState() == Managed.ManagedState.Managed) {
-                    hostMetrics.incrUpResources();
-                }
-
-                for (final Host host: hostDao.findByClusterId(cluster.getId())) {
-                    if (host == null || host.getType() != Host.Type.Routing) {
+            if (AllowListMetricsComputation.value()) {
+                for (final Cluster cluster : clusterDao.listClustersByDcId(zoneId)) {
+                    if (cluster == null) {
                         continue;
                     }
-                    updateHostMetrics(hostMetrics, hostJoinDao.findById(host.getId()));
+                    for (final Host host: hostDao.findByClusterId(cluster.getId())) {
+                        if (host == null || host.getType() != Host.Type.Routing) {
+                            continue;
+                        }
+                        updateHostMetrics(hostMetrics, hostJoinDao.findById(host.getId()));
+                    }
+                }
+            } else {
+                if (cpuCapacity != null) {
+                    hostMetrics.setCpuAllocated(cpuCapacity.getAllocatedCapacity());
+                }
+                if (memoryCapacity != null) {
+                    hostMetrics.setMemoryAllocated(memoryCapacity.getAllocatedCapacity());
                 }
             }
 
+            addHostCpuMetricsToResponse(metricsResponse, null, hostMetrics);
+            addHostMemoryMetricsToResponse(metricsResponse, null, hostMetrics);
+
             metricsResponse.setHasAnnotation(zoneResponse.hasAnnotation());
             metricsResponse.setState(zoneResponse.getAllocationState());
             metricsResponse.setResource(hostMetrics.getUpResources(), hostMetrics.getTotalResources());
 
-            final Long totalHosts = hostMetrics.getTotalHosts();
-            // CPU
-            addHostCpuMetricsToResponse(metricsResponse, null, hostMetrics);
-            // Memory
-            addHostMemoryMetricsToResponse(metricsResponse, null, hostMetrics);
-
             metricsResponses.add(metricsResponse);
         }
         return metricsResponses;
@@ -1028,12 +1030,14 @@ public DbMetricsResponse listDbMetrics() {
 
     private void getQueryHistory(DbMetricsResponse response) {
         Map<String, Object> dbStats = ApiDBUtils.getDbStatistics();
-        if (dbStats != null) {
-            response.setQueries((Long)dbStats.get(DbStatsCollection.queries));
-            response.setUptime((Long)dbStats.get(DbStatsCollection.uptime));
+        if (dbStats == null) {
+            return;
         }
 
-        List<Double> loadHistory = (List<Double>) dbStats.get(DbStatsCollection.loadAvarages);
+        response.setQueries((Long)dbStats.getOrDefault(DbStatsCollection.queries, -1L));
+        response.setUptime((Long)dbStats.getOrDefault(DbStatsCollection.uptime, -1L));
+
+        List<Double> loadHistory = (List<Double>) dbStats.getOrDefault(DbStatsCollection.loadAvarages, new ArrayList<Double>());
         double[] loadAverages = new double[loadHistory.size()];
 
         int index = 0;
@@ -1108,6 +1112,16 @@ public List<Class<?>> getCommands() {
         return cmdList;
     }
 
+    @Override
+    public String getConfigComponentName() {
+        return MetricsService.class.getSimpleName();
+    }
+
+    @Override
+    public ConfigKey<?>[] getConfigKeys() {
+        return new ConfigKey<?>[] {AllowListMetricsComputation};
+    }
+
     private class HostMetrics {
         // CPU metrics
         private Long totalCpu = 0L;
@@ -1133,6 +1147,14 @@ public HostMetrics(final CapacityDaoImpl.SummedCapacity totalCpu, final Capacity
             }
         }
 
+        public void setCpuAllocated(Long cpuAllocated) {
+            this.cpuAllocated = cpuAllocated;
+        }
+
+        public void setMemoryAllocated(Long memoryAllocated) {
+            this.memoryAllocated = memoryAllocated;
+        }
+
         public void addCpuAllocated(Long cpuAllocated) {
             this.cpuAllocated += cpuAllocated;
         }
@@ -1161,16 +1183,16 @@ public void setMaximumMemoryUsage(Long maximumMemoryUsage) {
             }
         }
 
-        public void incrTotalHosts() {
-            this.totalHosts++;
+        public void setTotalHosts(Long totalHosts) {
+            this.totalHosts = totalHosts;
         }
 
-        public void incrTotalResources() {
-            this.totalResources++;
+        public void setTotalResources(Long totalResources) {
+            this.totalResources = totalResources;
         }
 
-        public void incrUpResources() {
-            this.upResources++;
+        public void setUpResources(Long upResources) {
+            this.upResources = upResources;
         }
 
         public Long getTotalCpu() {
diff --git a/plugins/storage/volume/default/src/main/java/org/apache/cloudstack/storage/datastore/lifecycle/CloudStackPrimaryDataStoreLifeCycleImpl.java b/plugins/storage/volume/default/src/main/java/org/apache/cloudstack/storage/datastore/lifecycle/CloudStackPrimaryDataStoreLifeCycleImpl.java
index bc66e2ff1360..db6a8b4e778d 100644
--- a/plugins/storage/volume/default/src/main/java/org/apache/cloudstack/storage/datastore/lifecycle/CloudStackPrimaryDataStoreLifeCycleImpl.java
+++ b/plugins/storage/volume/default/src/main/java/org/apache/cloudstack/storage/datastore/lifecycle/CloudStackPrimaryDataStoreLifeCycleImpl.java
@@ -18,6 +18,26 @@
  */
 package org.apache.cloudstack.storage.datastore.lifecycle;
 
+import java.util.Collections;
+import java.util.List;
+import java.util.Map;
+import java.util.UUID;
+import java.util.stream.Collectors;
+
+import javax.inject.Inject;
+
+import org.apache.cloudstack.engine.subsystem.api.storage.ClusterScope;
+import org.apache.cloudstack.engine.subsystem.api.storage.DataStore;
+import org.apache.cloudstack.engine.subsystem.api.storage.DataStoreManager;
+import org.apache.cloudstack.engine.subsystem.api.storage.HostScope;
+import org.apache.cloudstack.engine.subsystem.api.storage.PrimaryDataStoreInfo;
+import org.apache.cloudstack.engine.subsystem.api.storage.PrimaryDataStoreLifeCycle;
+import org.apache.cloudstack.engine.subsystem.api.storage.PrimaryDataStoreParameters;
+import org.apache.cloudstack.engine.subsystem.api.storage.ZoneScope;
+import org.apache.cloudstack.storage.datastore.db.PrimaryDataStoreDao;
+import org.apache.cloudstack.storage.datastore.db.StoragePoolVO;
+import org.apache.cloudstack.storage.volume.datastore.PrimaryDataStoreHelper;
+
 import com.cloud.agent.AgentManager;
 import com.cloud.agent.api.Answer;
 import com.cloud.agent.api.CreateStoragePoolCommand;
@@ -45,6 +65,7 @@
 import com.cloud.storage.dao.VolumeDao;
 import com.cloud.user.dao.UserDao;
 import com.cloud.utils.NumbersUtil;
+import com.cloud.utils.Pair;
 import com.cloud.utils.db.DB;
 import com.cloud.utils.exception.CloudRuntimeException;
 import com.cloud.vm.VirtualMachineManager;
@@ -53,23 +74,6 @@
 import com.cloud.vm.dao.SecondaryStorageVmDao;
 import com.cloud.vm.dao.UserVmDao;
 import com.cloud.vm.dao.VMInstanceDao;
-import org.apache.cloudstack.engine.subsystem.api.storage.ClusterScope;
-import org.apache.cloudstack.engine.subsystem.api.storage.DataStore;
-import org.apache.cloudstack.engine.subsystem.api.storage.DataStoreManager;
-import org.apache.cloudstack.engine.subsystem.api.storage.HostScope;
-import org.apache.cloudstack.engine.subsystem.api.storage.PrimaryDataStoreInfo;
-import org.apache.cloudstack.engine.subsystem.api.storage.PrimaryDataStoreLifeCycle;
-import org.apache.cloudstack.engine.subsystem.api.storage.PrimaryDataStoreParameters;
-import org.apache.cloudstack.engine.subsystem.api.storage.ZoneScope;
-import org.apache.cloudstack.storage.datastore.db.PrimaryDataStoreDao;
-import org.apache.cloudstack.storage.datastore.db.StoragePoolVO;
-import org.apache.cloudstack.storage.volume.datastore.PrimaryDataStoreHelper;
-
-import javax.inject.Inject;
-import java.util.ArrayList;
-import java.util.List;
-import java.util.Map;
-import java.util.UUID;
 
 public class CloudStackPrimaryDataStoreLifeCycleImpl extends BasePrimaryDataStoreLifeCycleImpl implements PrimaryDataStoreLifeCycle {
     @Inject
@@ -318,16 +322,15 @@ public DataStore initialize(Map<String, Object> dsInfos) {
 
     private void validateVcenterDetails(Long zoneId, Long podId, Long clusterId, String storageHost) {
 
-        List<HostVO> allHosts =
-                _resourceMgr.listAllUpHosts(Host.Type.Routing, clusterId, podId, zoneId);
-        if (allHosts.isEmpty()) {
+        List<Long> allHostIds = _hostDao.listIdsForUpRouting(zoneId, podId, clusterId);
+        if (allHostIds.isEmpty()) {
             throw new CloudRuntimeException("No host up to associate a storage pool with in zone: " + zoneId + " pod: " + podId + " cluster: " + clusterId);
         }
 
         boolean success = false;
-        for (HostVO h : allHosts) {
+        for (Long hId : allHostIds) {
             ValidateVcenterDetailsCommand cmd = new ValidateVcenterDetailsCommand(storageHost);
-            final Answer answer = agentMgr.easySend(h.getId(), cmd);
+            final Answer answer = agentMgr.easySend(hId, cmd);
             if (answer != null && answer.getResult()) {
                 logger.info("Successfully validated vCenter details provided");
                 return;
@@ -335,8 +338,7 @@ private void validateVcenterDetails(Long zoneId, Long podId, Long clusterId, Str
                 if (answer != null) {
                     throw new InvalidParameterValueException("Provided vCenter server details does not match with the existing vCenter in zone id: " + zoneId);
                 } else {
-                    String msg = "Can not validate vCenter through host " + h.getId() + " due to ValidateVcenterDetailsCommand returns null";
-                    logger.warn(msg);
+                    logger.warn("Can not validate vCenter through host {} due to ValidateVcenterDetailsCommand returns null", hId);
                 }
             }
         }
@@ -373,85 +375,54 @@ protected boolean createStoragePool(long hostId, StoragePool pool) {
         }
     }
 
-    @Override
-    public boolean attachCluster(DataStore store, ClusterScope scope) {
-        PrimaryDataStoreInfo primarystore = (PrimaryDataStoreInfo)store;
-        // Check if there is host up in this cluster
-        List<HostVO> allHosts =
-                _resourceMgr.listAllUpHosts(Host.Type.Routing, primarystore.getClusterId(), primarystore.getPodId(), primarystore.getDataCenterId());
+    private Pair<List<Long>, Boolean> prepareOcfs2NodesIfNeeded(PrimaryDataStoreInfo primaryStore) {
+        if (!StoragePoolType.OCFS2.equals(primaryStore.getPoolType())) {
+            return new Pair<>(_hostDao.listIdsForUpRouting(primaryStore.getDataCenterId(),
+                    primaryStore.getPodId(), primaryStore.getClusterId()), true);
+        }
+        List<HostVO> allHosts = _resourceMgr.listAllUpHosts(Host.Type.Routing, primaryStore.getClusterId(),
+                primaryStore.getPodId(), primaryStore.getDataCenterId());
         if (allHosts.isEmpty()) {
-            primaryDataStoreDao.expunge(primarystore.getId());
-            throw new CloudRuntimeException("No host up to associate a storage pool with in cluster " + primarystore.getClusterId());
+            return new Pair<>(Collections.emptyList(), true);
+        }
+        List<Long> hostIds = allHosts.stream().map(HostVO::getId).collect(Collectors.toList());
+        if (!_ocfs2Mgr.prepareNodes(allHosts, primaryStore)) {
+            return new Pair<>(hostIds, false);
         }
+        return new Pair<>(hostIds, true);
+    }
 
-        if (primarystore.getPoolType() == StoragePoolType.OCFS2 && !_ocfs2Mgr.prepareNodes(allHosts, primarystore)) {
-            logger.warn("Can not create storage pool " + primarystore + " on cluster " + primarystore.getClusterId());
-            primaryDataStoreDao.expunge(primarystore.getId());
+    @Override
+    public boolean attachCluster(DataStore store, ClusterScope scope) {
+        PrimaryDataStoreInfo primaryStore = (PrimaryDataStoreInfo)store;
+        Pair<List<Long>, Boolean> result = prepareOcfs2NodesIfNeeded(primaryStore);
+        List<Long> hostIds = result.first();
+        if (hostIds.isEmpty()) {
+            primaryDataStoreDao.expunge(primaryStore.getId());
+            throw new CloudRuntimeException("No host up to associate a storage pool with in cluster " + primaryStore.getClusterId());
+        }
+        if (!result.second()) {
+            logger.warn("Can not create storage pool {} on cluster {}", primaryStore, primaryStore.getClusterId());
+            primaryDataStoreDao.expunge(primaryStore.getId());
             return false;
         }
-
-        boolean success = false;
-        for (HostVO h : allHosts) {
-            success = createStoragePool(h.getId(), primarystore);
-            if (success) {
+        for (Long hId : hostIds) {
+            if (createStoragePool(hId, primaryStore)) {
                 break;
             }
         }
-
         logger.debug("In createPool Adding the pool to each of the hosts");
-        List<HostVO> poolHosts = new ArrayList<HostVO>();
-        for (HostVO h : allHosts) {
-            try {
-                storageMgr.connectHostToSharedPool(h.getId(), primarystore.getId());
-                poolHosts.add(h);
-            } catch (StorageConflictException se) {
-                primaryDataStoreDao.expunge(primarystore.getId());
-                throw new CloudRuntimeException("Storage has already been added as local storage");
-            } catch (Exception e) {
-                logger.warn("Unable to establish a connection between " + h + " and " + primarystore, e);
-                String reason = storageMgr.getStoragePoolMountFailureReason(e.getMessage());
-                if (reason != null) {
-                    throw new CloudRuntimeException(reason);
-                }
-            }
-        }
-
-        if (poolHosts.isEmpty()) {
-            logger.warn("No host can access storage pool " + primarystore + " on cluster " + primarystore.getClusterId());
-            primaryDataStoreDao.expunge(primarystore.getId());
-            throw new CloudRuntimeException("Failed to access storage pool");
-        }
-
+        storageMgr.connectHostsToPool(store, hostIds, scope, true, true);
         dataStoreHelper.attachCluster(store);
         return true;
     }
 
     @Override
-    public boolean attachZone(DataStore dataStore, ZoneScope scope, HypervisorType hypervisorType) {
-        List<HostVO> hosts = _resourceMgr.listAllUpHostsInOneZoneByHypervisor(hypervisorType, scope.getScopeId());
+    public boolean attachZone(DataStore store, ZoneScope scope, HypervisorType hypervisorType) {
+        List<Long> hostIds = _hostDao.listIdsForUpEnabledByZoneAndHypervisor(scope.getScopeId(), hypervisorType);
         logger.debug("In createPool. Attaching the pool to each of the hosts.");
-        List<HostVO> poolHosts = new ArrayList<HostVO>();
-        for (HostVO host : hosts) {
-            try {
-                storageMgr.connectHostToSharedPool(host.getId(), dataStore.getId());
-                poolHosts.add(host);
-            } catch (StorageConflictException se) {
-                    primaryDataStoreDao.expunge(dataStore.getId());
-                    throw new CloudRuntimeException("Storage has already been added as local storage to host: " + host.getName());
-            } catch (Exception e) {
-                logger.warn("Unable to establish a connection between " + host + " and " + dataStore, e);
-                String reason = storageMgr.getStoragePoolMountFailureReason(e.getMessage());
-                if (reason != null) {
-                    throw new CloudRuntimeException(reason);
-                }
-            }
-        }
-        if (poolHosts.isEmpty()) {
-            logger.warn("No host can access storage pool " + dataStore + " in this zone.");
-            primaryDataStoreDao.expunge(dataStore.getId());
-            throw new CloudRuntimeException("Failed to create storage pool as it is not accessible to hosts.");
-        }
-        dataStoreHelper.attachZone(dataStore, hypervisorType);
+        storageMgr.connectHostsToPool(store, hostIds, scope, true, true);
+        dataStoreHelper.attachZone(store, hypervisorType);
         return true;
     }
 
diff --git a/plugins/storage/volume/default/src/test/java/org/apache/cloudstack/storage/datastore/lifecycle/CloudStackPrimaryDataStoreLifeCycleImplTest.java b/plugins/storage/volume/default/src/test/java/org/apache/cloudstack/storage/datastore/lifecycle/CloudStackPrimaryDataStoreLifeCycleImplTest.java
index 924c98b7912f..44f088babdc6 100644
--- a/plugins/storage/volume/default/src/test/java/org/apache/cloudstack/storage/datastore/lifecycle/CloudStackPrimaryDataStoreLifeCycleImplTest.java
+++ b/plugins/storage/volume/default/src/test/java/org/apache/cloudstack/storage/datastore/lifecycle/CloudStackPrimaryDataStoreLifeCycleImplTest.java
@@ -27,6 +27,7 @@
 import com.cloud.host.Host;
 import com.cloud.host.HostVO;
 import com.cloud.host.Status;
+import com.cloud.host.dao.HostDao;
 import com.cloud.resource.ResourceManager;
 import com.cloud.resource.ResourceState;
 import com.cloud.storage.DataStoreRole;
@@ -61,6 +62,7 @@
 import java.util.ArrayList;
 import java.util.List;
 import java.util.UUID;
+import java.util.stream.Collectors;
 
 import static org.mockito.ArgumentMatchers.anyLong;
 import static org.mockito.ArgumentMatchers.anyString;
@@ -118,6 +120,9 @@ public class CloudStackPrimaryDataStoreLifeCycleImplTest extends TestCase {
     @Mock
     PrimaryDataStoreHelper primaryDataStoreHelper;
 
+    @Mock
+    HostDao hostDao;
+
     AutoCloseable closeable;
 
     @Before
@@ -132,7 +137,7 @@ public void initMocks() throws StorageConflictException {
         List<HostVO> hostList = new ArrayList<HostVO>();
         HostVO host1 = new HostVO(1L, "aa01", Host.Type.Routing, "192.168.1.1", "255.255.255.0", null, null, null, null, null, null, null, null, null, null,
                 UUID.randomUUID().toString(), Status.Up, "1.0", null, null, 1L, null, 0, 0, "aa", 0, Storage.StoragePoolType.NetworkFilesystem);
-        HostVO host2 = new HostVO(1L, "aa02", Host.Type.Routing, "192.168.1.1", "255.255.255.0", null, null, null, null, null, null, null, null, null, null,
+        HostVO host2 = new HostVO(2L, "aa02", Host.Type.Routing, "192.168.1.1", "255.255.255.0", null, null, null, null, null, null, null, null, null, null,
                 UUID.randomUUID().toString(), Status.Up, "1.0", null, null, 1L, null, 0, 0, "aa", 0, Storage.StoragePoolType.NetworkFilesystem);
 
         host1.setResourceState(ResourceState.Enabled);
@@ -154,7 +159,10 @@ public void initMocks() throws StorageConflictException {
         storageMgr.registerHostListener("default", hostListener);
 
 
-        when(_resourceMgr.listAllUpHosts(eq(Host.Type.Routing), anyLong(), anyLong(), anyLong())).thenReturn(hostList);
+        when(hostDao.listIdsForUpRouting(anyLong(), anyLong(), anyLong()))
+                .thenReturn(hostList.stream().map(HostVO::getId).collect(Collectors.toList()));
+        when(hostDao.findById(host1.getId())).thenReturn(host1);
+        when(hostDao.findById(host2.getId())).thenReturn(host2);
         when(agentMgr.easySend(anyLong(), Mockito.any(ModifyStoragePoolCommand.class))).thenReturn(answer);
         when(answer.getResult()).thenReturn(true);
 
diff --git a/plugins/storage/volume/scaleio/src/main/java/org/apache/cloudstack/storage/datastore/lifecycle/ScaleIOPrimaryDataStoreLifeCycle.java b/plugins/storage/volume/scaleio/src/main/java/org/apache/cloudstack/storage/datastore/lifecycle/ScaleIOPrimaryDataStoreLifeCycle.java
index 7bbe0331c071..1ce5accc90e8 100644
--- a/plugins/storage/volume/scaleio/src/main/java/org/apache/cloudstack/storage/datastore/lifecycle/ScaleIOPrimaryDataStoreLifeCycle.java
+++ b/plugins/storage/volume/scaleio/src/main/java/org/apache/cloudstack/storage/datastore/lifecycle/ScaleIOPrimaryDataStoreLifeCycle.java
@@ -24,17 +24,12 @@
 import java.net.URLDecoder;
 import java.security.KeyManagementException;
 import java.security.NoSuchAlgorithmException;
-import java.util.ArrayList;
 import java.util.List;
 import java.util.Map;
 import java.util.UUID;
 
 import javax.inject.Inject;
 
-import org.apache.cloudstack.storage.datastore.client.ScaleIOGatewayClientConnectionPool;
-import org.apache.cloudstack.storage.datastore.db.StoragePoolDetailsDao;
-import org.apache.cloudstack.storage.datastore.util.ScaleIOUtil;
-import org.apache.commons.collections.CollectionUtils;
 import org.apache.cloudstack.engine.subsystem.api.storage.ClusterScope;
 import org.apache.cloudstack.engine.subsystem.api.storage.DataStore;
 import org.apache.cloudstack.engine.subsystem.api.storage.HostScope;
@@ -44,9 +39,13 @@
 import org.apache.cloudstack.engine.subsystem.api.storage.ZoneScope;
 import org.apache.cloudstack.storage.datastore.api.StoragePoolStatistics;
 import org.apache.cloudstack.storage.datastore.client.ScaleIOGatewayClient;
+import org.apache.cloudstack.storage.datastore.client.ScaleIOGatewayClientConnectionPool;
 import org.apache.cloudstack.storage.datastore.db.PrimaryDataStoreDao;
+import org.apache.cloudstack.storage.datastore.db.StoragePoolDetailsDao;
 import org.apache.cloudstack.storage.datastore.db.StoragePoolVO;
+import org.apache.cloudstack.storage.datastore.util.ScaleIOUtil;
 import org.apache.cloudstack.storage.volume.datastore.PrimaryDataStoreHelper;
+import org.apache.commons.collections.CollectionUtils;
 
 import com.cloud.agent.AgentManager;
 import com.cloud.agent.api.Answer;
@@ -56,8 +55,7 @@
 import com.cloud.dc.ClusterVO;
 import com.cloud.dc.dao.ClusterDao;
 import com.cloud.exception.InvalidParameterValueException;
-import com.cloud.host.Host;
-import com.cloud.host.HostVO;
+import com.cloud.host.dao.HostDao;
 import com.cloud.hypervisor.Hypervisor;
 import com.cloud.resource.ResourceManager;
 import com.cloud.storage.Storage;
@@ -77,6 +75,8 @@ public class ScaleIOPrimaryDataStoreLifeCycle extends BasePrimaryDataStoreLifeCy
     @Inject
     private ClusterDao clusterDao;
     @Inject
+    private HostDao hostDao;
+    @Inject
     private PrimaryDataStoreDao primaryDataStoreDao;
     @Inject
     private StoragePoolDetailsDao storagePoolDetailsDao;
@@ -258,28 +258,15 @@ public boolean attachCluster(DataStore dataStore, ClusterScope scope) {
         }
 
         PrimaryDataStoreInfo primaryDataStoreInfo = (PrimaryDataStoreInfo) dataStore;
-        List<HostVO> hostsInCluster = resourceManager.listAllUpAndEnabledHosts(Host.Type.Routing, primaryDataStoreInfo.getClusterId(),
-                primaryDataStoreInfo.getPodId(), primaryDataStoreInfo.getDataCenterId());
-        if (hostsInCluster.isEmpty()) {
+        List<Long> hostIds = hostDao.listIdsForUpRouting(primaryDataStoreInfo.getDataCenterId(),
+                primaryDataStoreInfo.getPodId(), primaryDataStoreInfo.getClusterId());
+        if (hostIds.isEmpty()) {
             primaryDataStoreDao.expunge(primaryDataStoreInfo.getId());
             throw new CloudRuntimeException("No hosts are Up to associate a storage pool with in cluster: " + primaryDataStoreInfo.getClusterId());
         }
 
-        logger.debug("Attaching the pool to each of the hosts in the cluster: " + primaryDataStoreInfo.getClusterId());
-        List<HostVO> poolHosts = new ArrayList<HostVO>();
-        for (HostVO host : hostsInCluster) {
-            try {
-                if (storageMgr.connectHostToSharedPool(host.getId(), primaryDataStoreInfo.getId())) {
-                    poolHosts.add(host);
-                }
-            } catch (Exception e) {
-                logger.warn("Unable to establish a connection between host: " + host + " and pool: " + dataStore + "on the cluster: " + primaryDataStoreInfo.getClusterId(), e);
-            }
-        }
-
-        if (poolHosts.isEmpty()) {
-            logger.warn("No host can access storage pool '" + primaryDataStoreInfo + "' on cluster '" + primaryDataStoreInfo.getClusterId() + "'.");
-        }
+        logger.debug("Attaching the pool to each of the hosts in the cluster: {}", primaryDataStoreInfo.getClusterId());
+        storageMgr.connectHostsToPool(dataStore, hostIds, scope, false, false);
 
         dataStoreHelper.attachCluster(dataStore);
         return true;
@@ -296,21 +283,9 @@ public boolean attachZone(DataStore dataStore, ZoneScope scope, Hypervisor.Hyper
             throw new CloudRuntimeException("Unsupported hypervisor type: " + hypervisorType.toString());
         }
 
-        logger.debug("Attaching the pool to each of the hosts in the zone: " + scope.getScopeId());
-        List<HostVO> hosts = resourceManager.listAllUpAndEnabledHostsInOneZoneByHypervisor(hypervisorType, scope.getScopeId());
-        List<HostVO> poolHosts = new ArrayList<HostVO>();
-        for (HostVO host : hosts) {
-            try {
-                if (storageMgr.connectHostToSharedPool(host.getId(), dataStore.getId())) {
-                    poolHosts.add(host);
-                }
-            } catch (Exception e) {
-                logger.warn("Unable to establish a connection between host: " + host + " and pool: " + dataStore + "in the zone: " + scope.getScopeId(), e);
-            }
-        }
-        if (poolHosts.isEmpty()) {
-            logger.warn("No host can access storage pool " + dataStore + " in the zone: " + scope.getScopeId());
-        }
+        logger.debug("Attaching the pool to each of the hosts in the zone: {}", scope.getScopeId());
+        List<Long> hostIds = hostDao.listIdsForUpRouting(null, null, scope.getScopeId());
+        storageMgr.connectHostsToPool(dataStore, hostIds, scope, false, false);
 
         dataStoreHelper.attachZone(dataStore);
         return true;
diff --git a/plugins/storage/volume/storpool/src/main/java/org/apache/cloudstack/storage/datastore/util/StorPoolHelper.java b/plugins/storage/volume/storpool/src/main/java/org/apache/cloudstack/storage/datastore/util/StorPoolHelper.java
index 3113ae8fdaaf..f13d296af3b0 100644
--- a/plugins/storage/volume/storpool/src/main/java/org/apache/cloudstack/storage/datastore/util/StorPoolHelper.java
+++ b/plugins/storage/volume/storpool/src/main/java/org/apache/cloudstack/storage/datastore/util/StorPoolHelper.java
@@ -219,17 +219,17 @@ public static void setSpClusterIdIfNeeded(long hostId, String clusterId, Cluster
     }
 
     public static Long findClusterIdByGlobalId(String globalId, ClusterDao clusterDao) {
-        List<ClusterVO> clusterVo = clusterDao.listAll();
-        if (clusterVo.size() == 1) {
+        List<Long> clusterIds = clusterDao.listAllIds();
+        if (clusterIds.size() == 1) {
             StorPoolUtil.spLog("There is only one cluster, sending backup to secondary command");
             return null;
         }
-        for (ClusterVO clusterVO2 : clusterVo) {
-            if (globalId != null && StorPoolConfigurationManager.StorPoolClusterId.valueIn(clusterVO2.getId()) != null
-                    && globalId.contains(StorPoolConfigurationManager.StorPoolClusterId.valueIn(clusterVO2.getId()).toString())) {
-                StorPoolUtil.spLog("Found cluster with id=%s for object with globalId=%s", clusterVO2.getId(),
+        for (Long clusterId : clusterIds) {
+            if (globalId != null && StorPoolConfigurationManager.StorPoolClusterId.valueIn(clusterId) != null
+                    && globalId.contains(StorPoolConfigurationManager.StorPoolClusterId.valueIn(clusterId))) {
+                StorPoolUtil.spLog("Found cluster with id=%s for object with globalId=%s", clusterId,
                         globalId);
-                return clusterVO2.getId();
+                return clusterId;
             }
         }
         throw new CloudRuntimeException(
diff --git a/server/src/main/java/com/cloud/alert/AlertManagerImpl.java b/server/src/main/java/com/cloud/alert/AlertManagerImpl.java
index 4c4f08f12bd7..0fc726f78474 100644
--- a/server/src/main/java/com/cloud/alert/AlertManagerImpl.java
+++ b/server/src/main/java/com/cloud/alert/AlertManagerImpl.java
@@ -26,8 +26,11 @@
 import java.util.Map;
 import java.util.Set;
 import java.util.Timer;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.ExecutionException;
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
+import java.util.concurrent.Future;
 
 import javax.inject.Inject;
 import javax.mail.MessagingException;
@@ -72,12 +75,11 @@
 import com.cloud.event.EventTypes;
 import com.cloud.host.Host;
 import com.cloud.host.HostVO;
+import com.cloud.host.dao.HostDao;
 import com.cloud.network.Ipv6Service;
 import com.cloud.network.dao.IPAddressDao;
 import com.cloud.org.Grouping.AllocationState;
 import com.cloud.resource.ResourceManager;
-import com.cloud.service.ServiceOfferingVO;
-import com.cloud.service.dao.ServiceOfferingDao;
 import com.cloud.storage.StorageManager;
 import com.cloud.utils.Pair;
 import com.cloud.utils.component.ManagerBase;
@@ -121,9 +123,9 @@ public class AlertManagerImpl extends ManagerBase implements AlertManager, Confi
     @Inject
     protected ConfigDepot _configDepot;
     @Inject
-    ServiceOfferingDao _offeringsDao;
-    @Inject
     Ipv6Service ipv6Service;
+    @Inject
+    HostDao hostDao;
 
     private Timer _timer = null;
     private long _capacityCheckPeriod = 60L * 60L * 1000L; // One hour by default.
@@ -257,6 +259,64 @@ public void sendAlert(AlertType alertType, long dataCenterId, Long podId, String
         }
     }
 
+    protected void recalculateHostCapacities() {
+        // Calculate CPU and RAM capacities
+        List<Long> hostIds = hostDao.listIdsByType(Host.Type.Routing);
+        if (hostIds.isEmpty()) {
+            return;
+        }
+        ConcurrentHashMap<Long, Future<Void>> futures = new ConcurrentHashMap<>();
+        ExecutorService executorService = Executors.newFixedThreadPool(Math.max(1,
+                Math.min(CapacityManager.CapacityCalculateWorkers.value(), hostIds.size())));
+        for (Long hostId : hostIds) {
+            futures.put(hostId, executorService.submit(() -> {
+                final HostVO host = hostDao.findById(hostId);
+                _capacityMgr.updateCapacityForHost(host);
+                return null;
+            }));
+        }
+        for (Map.Entry<Long, Future<Void>> entry: futures.entrySet()) {
+            try {
+                entry.getValue().get();
+            } catch (InterruptedException | ExecutionException e) {
+                logger.error(String.format("Error during capacity calculation for host: %d due to : %s",
+                        entry.getKey(), e.getMessage()), e);
+            }
+        }
+        executorService.shutdown();
+    }
+
+    protected void recalculateStorageCapacities() {
+        List<Long> storagePoolIds = _storagePoolDao.listAllIds();
+        if (storagePoolIds.isEmpty()) {
+            return;
+        }
+        ConcurrentHashMap<Long, Future<Void>> futures = new ConcurrentHashMap<>();
+        ExecutorService executorService = Executors.newFixedThreadPool(Math.max(1,
+                Math.min(CapacityManager.CapacityCalculateWorkers.value(), storagePoolIds.size())));
+        for (Long poolId: storagePoolIds) {
+            futures.put(poolId, executorService.submit(() -> {
+                final StoragePoolVO pool = _storagePoolDao.findById(poolId);
+                long disk = _capacityMgr.getAllocatedPoolCapacity(pool, null);
+                if (pool.isShared()) {
+                    _storageMgr.createCapacityEntry(pool, Capacity.CAPACITY_TYPE_STORAGE_ALLOCATED, disk);
+                } else {
+                    _storageMgr.createCapacityEntry(pool, Capacity.CAPACITY_TYPE_LOCAL_STORAGE, disk);
+                }
+                return null;
+            }));
+        }
+        for (Map.Entry<Long, Future<Void>> entry: futures.entrySet()) {
+            try {
+                entry.getValue().get();
+            } catch (InterruptedException | ExecutionException e) {
+                logger.error(String.format("Error during capacity calculation for storage pool: %d due to : %s",
+                        entry.getKey(), e.getMessage()), e);
+            }
+        }
+        executorService.shutdown();
+    }
+
     @Override
     public void recalculateCapacity() {
         // FIXME: the right way to do this is to register a listener (see RouterStatsListener, VMSyncListener)
@@ -272,36 +332,14 @@ public void recalculateCapacity() {
                 logger.debug("recalculating system capacity");
                 logger.debug("Executing cpu/ram capacity update");
             }
-
             // Calculate CPU and RAM capacities
-            //     get all hosts...even if they are not in 'UP' state
-            List<HostVO> hosts = _resourceMgr.listAllNotInMaintenanceHostsInOneZone(Host.Type.Routing, null);
-            if (hosts != null) {
-                // prepare the service offerings
-                List<ServiceOfferingVO> offerings = _offeringsDao.listAllIncludingRemoved();
-                Map<Long, ServiceOfferingVO> offeringsMap = new HashMap<Long, ServiceOfferingVO>();
-                for (ServiceOfferingVO offering : offerings) {
-                    offeringsMap.put(offering.getId(), offering);
-                }
-                for (HostVO host : hosts) {
-                    _capacityMgr.updateCapacityForHost(host, offeringsMap);
-                }
-            }
+            recalculateHostCapacities();
             if (logger.isDebugEnabled()) {
                 logger.debug("Done executing cpu/ram capacity update");
                 logger.debug("Executing storage capacity update");
             }
             // Calculate storage pool capacity
-            List<StoragePoolVO> storagePools = _storagePoolDao.listAll();
-            for (StoragePoolVO pool : storagePools) {
-                long disk = _capacityMgr.getAllocatedPoolCapacity(pool, null);
-                if (pool.isShared()) {
-                    _storageMgr.createCapacityEntry(pool, Capacity.CAPACITY_TYPE_STORAGE_ALLOCATED, disk);
-                } else {
-                    _storageMgr.createCapacityEntry(pool, Capacity.CAPACITY_TYPE_LOCAL_STORAGE, disk);
-                }
-            }
-
+            recalculateStorageCapacities();
             if (logger.isDebugEnabled()) {
                 logger.debug("Done executing storage capacity update");
                 logger.debug("Executing capacity updates for public ip and Vlans");
diff --git a/server/src/main/java/com/cloud/api/query/QueryManagerImpl.java b/server/src/main/java/com/cloud/api/query/QueryManagerImpl.java
index 046c3c1e6bce..c9f4affba232 100644
--- a/server/src/main/java/com/cloud/api/query/QueryManagerImpl.java
+++ b/server/src/main/java/com/cloud/api/query/QueryManagerImpl.java
@@ -2332,7 +2332,7 @@ public Pair<List<Long>, Integer> searchForServerIdsAndCount(ListHostsCmd cmd) {
         // ids
         hostSearchBuilder.and("id", hostSearchBuilder.entity().getId(), SearchCriteria.Op.EQ);
         hostSearchBuilder.and("name", hostSearchBuilder.entity().getName(), SearchCriteria.Op.EQ);
-        hostSearchBuilder.and("type", hostSearchBuilder.entity().getType(), SearchCriteria.Op.LIKE);
+        hostSearchBuilder.and("type", hostSearchBuilder.entity().getType(), SearchCriteria.Op.EQ);
         hostSearchBuilder.and("status", hostSearchBuilder.entity().getStatus(), SearchCriteria.Op.EQ);
         hostSearchBuilder.and("dataCenterId", hostSearchBuilder.entity().getDataCenterId(), SearchCriteria.Op.EQ);
         hostSearchBuilder.and("podId", hostSearchBuilder.entity().getPodId(), SearchCriteria.Op.EQ);
@@ -2384,7 +2384,7 @@ public Pair<List<Long>, Integer> searchForServerIdsAndCount(ListHostsCmd cmd) {
             sc.setParameters("name", name);
         }
         if (type != null) {
-            sc.setParameters("type", "%" + type);
+            sc.setParameters("type", type);
         }
         if (state != null) {
             sc.setParameters("status", state);
@@ -4521,7 +4521,7 @@ private Pair<List<TemplateJoinVO>, Integer> searchForTemplatesInternal(Long temp
         // check if zone is configured, if not, just return empty list
         List<HypervisorType> hypers = null;
         if (!isIso) {
-            hypers = _resourceMgr.listAvailHypervisorInZone(null, null);
+            hypers = _resourceMgr.listAvailHypervisorInZone(null);
             if (hypers == null || hypers.isEmpty()) {
                 return new Pair<List<TemplateJoinVO>, Integer>(new ArrayList<TemplateJoinVO>(), 0);
             }
diff --git a/server/src/main/java/com/cloud/api/query/dao/UserVmJoinDao.java b/server/src/main/java/com/cloud/api/query/dao/UserVmJoinDao.java
index b4427a6315a9..58b73096de80 100644
--- a/server/src/main/java/com/cloud/api/query/dao/UserVmJoinDao.java
+++ b/server/src/main/java/com/cloud/api/query/dao/UserVmJoinDao.java
@@ -44,6 +44,6 @@ UserVmResponse newUserVmResponse(ResponseView view, String objectName, UserVmJoi
 
     List<UserVmJoinVO> listActiveByIsoId(Long isoId);
 
-    List<UserVmJoinVO> listByAccountServiceOfferingTemplateAndNotInState(long accountId, List<VirtualMachine.State> states,
-            List<Long> offeringIds, List<Long> templateIds);
+    List<UserVmJoinVO> listByAccountServiceOfferingTemplateAndNotInState(long accountId,
+             List<VirtualMachine.State> states, List<Long> offeringIds, List<Long> templateIds);
 }
diff --git a/server/src/main/java/com/cloud/api/query/dao/UserVmJoinDaoImpl.java b/server/src/main/java/com/cloud/api/query/dao/UserVmJoinDaoImpl.java
index af26a242db47..7e10df24e1b5 100644
--- a/server/src/main/java/com/cloud/api/query/dao/UserVmJoinDaoImpl.java
+++ b/server/src/main/java/com/cloud/api/query/dao/UserVmJoinDaoImpl.java
@@ -693,6 +693,8 @@ public List<UserVmJoinVO> newUserVmView(VirtualMachine... vms) {
     public List<UserVmJoinVO> listByAccountServiceOfferingTemplateAndNotInState(long accountId, List<State> states,
             List<Long> offeringIds, List<Long> templateIds) {
         SearchBuilder<UserVmJoinVO> userVmSearch = createSearchBuilder();
+        userVmSearch.selectFields(userVmSearch.entity().getId(), userVmSearch.entity().getCpu(),
+                userVmSearch.entity().getRamSize());
         userVmSearch.and("accountId", userVmSearch.entity().getAccountId(), Op.EQ);
         userVmSearch.and("serviceOfferingId", userVmSearch.entity().getServiceOfferingId(), Op.IN);
         userVmSearch.and("templateId", userVmSearch.entity().getTemplateId(), Op.IN);
@@ -713,6 +715,6 @@ public List<UserVmJoinVO> listByAccountServiceOfferingTemplateAndNotInState(long
             sc.setParameters("state", states.toArray());
         }
         sc.setParameters("displayVm", 1);
-        return listBy(sc);
+        return customSearch(sc, null);
     }
 }
diff --git a/server/src/main/java/com/cloud/capacity/CapacityManagerImpl.java b/server/src/main/java/com/cloud/capacity/CapacityManagerImpl.java
index 421c980b2096..0af57a87c4e2 100644
--- a/server/src/main/java/com/cloud/capacity/CapacityManagerImpl.java
+++ b/server/src/main/java/com/cloud/capacity/CapacityManagerImpl.java
@@ -23,6 +23,7 @@
 import java.util.List;
 import java.util.Map;
 import java.util.Optional;
+import java.util.stream.Collectors;
 
 import javax.inject.Inject;
 import javax.naming.ConfigurationException;
@@ -37,6 +38,10 @@
 import org.apache.cloudstack.framework.messagebus.MessageBus;
 import org.apache.cloudstack.framework.messagebus.PublishScope;
 import org.apache.cloudstack.storage.datastore.db.StoragePoolVO;
+import org.apache.cloudstack.utils.cache.LazyCache;
+import org.apache.cloudstack.utils.cache.SingleCache;
+import org.apache.commons.collections.CollectionUtils;
+import org.apache.commons.lang3.ObjectUtils;
 
 import com.cloud.agent.AgentManager;
 import com.cloud.agent.Listener;
@@ -50,7 +55,6 @@
 import com.cloud.configuration.Config;
 import com.cloud.dc.ClusterDetailsDao;
 import com.cloud.dc.ClusterDetailsVO;
-import com.cloud.dc.ClusterVO;
 import com.cloud.dc.dao.ClusterDao;
 import com.cloud.deploy.DeploymentClusterPlanner;
 import com.cloud.event.UsageEventVO;
@@ -141,6 +145,9 @@ public class CapacityManagerImpl extends ManagerBase implements CapacityManager,
     @Inject
     MessageBus _messageBus;
 
+    private LazyCache<Long, Pair<String, String>> clusterValuesCache;
+    private SingleCache<Map<Long, ServiceOfferingVO>> serviceOfferingsCache;
+
     @Override
     public boolean configure(String name, Map<String, Object> params) throws ConfigurationException {
         _vmCapacityReleaseInterval = NumbersUtil.parseInt(_configDao.getValue(Config.CapacitySkipcountingHours.key()), 3600);
@@ -156,6 +163,8 @@ public boolean configure(String name, Map<String, Object> params) throws Configu
     public boolean start() {
         _resourceMgr.registerResourceEvent(ResourceListener.EVENT_PREPARE_MAINTENANCE_AFTER, this);
         _resourceMgr.registerResourceEvent(ResourceListener.EVENT_CANCEL_MAINTENANCE_AFTER, this);
+        clusterValuesCache = new LazyCache<>(128, 60, this::getClusterValues);
+        serviceOfferingsCache = new SingleCache<>(60, this::getServiceOfferingsMap);
         return true;
     }
 
@@ -209,8 +218,8 @@ public void doInTransactionWithoutResult(TransactionStatus status) {
                     long reservedMem = capacityMemory.getReservedCapacity();
                     long reservedCpuCore = capacityCpuCore.getReservedCapacity();
                     long actualTotalCpu = capacityCpu.getTotalCapacity();
-                    float cpuOvercommitRatio = Float.parseFloat(_clusterDetailsDao.findDetail(clusterIdFinal, "cpuOvercommitRatio").getValue());
-                    float memoryOvercommitRatio = Float.parseFloat(_clusterDetailsDao.findDetail(clusterIdFinal, "memoryOvercommitRatio").getValue());
+                    float cpuOvercommitRatio = Float.parseFloat(_clusterDetailsDao.findDetail(clusterIdFinal, VmDetailConstants.CPU_OVER_COMMIT_RATIO).getValue());
+                    float memoryOvercommitRatio = Float.parseFloat(_clusterDetailsDao.findDetail(clusterIdFinal, VmDetailConstants.MEMORY_OVER_COMMIT_RATIO).getValue());
                     int vmCPU = svo.getCpu() * svo.getSpeed();
                     int vmCPUCore = svo.getCpu();
                     long vmMem = svo.getRamSize() * 1024L * 1024L;
@@ -284,8 +293,8 @@ public void allocateVmCapacity(VirtualMachine vm, final boolean fromLastHost) {
         final long hostId = vm.getHostId();
         final HostVO host = _hostDao.findById(hostId);
         final long clusterId = host.getClusterId();
-        final float cpuOvercommitRatio = Float.parseFloat(_clusterDetailsDao.findDetail(clusterId, "cpuOvercommitRatio").getValue());
-        final float memoryOvercommitRatio = Float.parseFloat(_clusterDetailsDao.findDetail(clusterId, "memoryOvercommitRatio").getValue());
+        final float cpuOvercommitRatio = Float.parseFloat(_clusterDetailsDao.findDetail(clusterId, VmDetailConstants.CPU_OVER_COMMIT_RATIO).getValue());
+        final float memoryOvercommitRatio = Float.parseFloat(_clusterDetailsDao.findDetail(clusterId, VmDetailConstants.MEMORY_OVER_COMMIT_RATIO).getValue());
 
         final ServiceOfferingVO svo = _offeringsDao.findById(vm.getId(), vm.getServiceOfferingId());
 
@@ -371,13 +380,13 @@ public void doInTransactionWithoutResult(TransactionStatus status) {
                         ",alloc_from_last:" + fromLastHost);
 
                     long cluster_id = host.getClusterId();
-                    ClusterDetailsVO cluster_detail_cpu = _clusterDetailsDao.findDetail(cluster_id, "cpuOvercommitRatio");
-                    ClusterDetailsVO cluster_detail_ram = _clusterDetailsDao.findDetail(cluster_id, "memoryOvercommitRatio");
+                    ClusterDetailsVO cluster_detail_cpu = _clusterDetailsDao.findDetail(cluster_id, VmDetailConstants.CPU_OVER_COMMIT_RATIO);
+                    ClusterDetailsVO cluster_detail_ram = _clusterDetailsDao.findDetail(cluster_id, VmDetailConstants.MEMORY_OVER_COMMIT_RATIO);
                     Float cpuOvercommitRatio = Float.parseFloat(cluster_detail_cpu.getValue());
                     Float memoryOvercommitRatio = Float.parseFloat(cluster_detail_ram.getValue());
 
                     boolean hostHasCpuCapability, hostHasCapacity = false;
-                    hostHasCpuCapability = checkIfHostHasCpuCapability(host.getId(), cpucore, cpuspeed);
+                    hostHasCpuCapability = checkIfHostHasCpuCapability(host, cpucore, cpuspeed);
 
                     if (hostHasCpuCapability) {
                         // first check from reserved capacity
@@ -407,23 +416,16 @@ public void doInTransactionWithoutResult(TransactionStatus status) {
     }
 
     @Override
-    public boolean checkIfHostHasCpuCapability(long hostId, Integer cpuNum, Integer cpuSpeed) {
-
+    public boolean checkIfHostHasCpuCapability(Host host, Integer cpuNum, Integer cpuSpeed) {
         // Check host can support the Cpu Number and Speed.
-        Host host = _hostDao.findById(hostId);
         boolean isCpuNumGood = host.getCpus().intValue() >= cpuNum;
         boolean isCpuSpeedGood = host.getSpeed().intValue() >= cpuSpeed;
         if (isCpuNumGood && isCpuSpeedGood) {
-            if (logger.isDebugEnabled()) {
-                logger.debug("Host: " + hostId + " has cpu capability (cpu:" + host.getCpus() + ", speed:" + host.getSpeed() +
-                    ") to support requested CPU: " + cpuNum + " and requested speed: " + cpuSpeed);
-            }
+            logger.debug("Host: {} has cpu capability (cpu: {}, speed: {} ) to support requested CPU: {} and requested speed: {}",
+                    host.getId(), host.getCpus(), host.getSpeed(), cpuNum, cpuSpeed);
             return true;
-        } else {
-            if (logger.isDebugEnabled()) {
-                logger.debug("Host: " + hostId + " doesn't have cpu capability (cpu:" + host.getCpus() + ", speed:" + host.getSpeed() +
-                    ") to support requested CPU: " + cpuNum + " and requested speed: " + cpuSpeed);
-            }
+        } else {logger.debug("Host: {} doesn't have cpu capability (cpu: {}, speed: {} ) to support requested CPU: {} and requested speed: {}",
+                host.getId(), host.getCpus(), host.getSpeed(), cpuNum, cpuSpeed);
             return false;
         }
     }
@@ -630,21 +632,50 @@ public long getAllocatedPoolCapacity(StoragePoolVO pool, VMTemplateVO templateFo
         return totalAllocatedSize;
     }
 
-    @DB
-    @Override
-    public void updateCapacityForHost(final Host host) {
-        // prepare the service offerings
-        List<ServiceOfferingVO> offerings = _offeringsDao.listAllIncludingRemoved();
-        Map<Long, ServiceOfferingVO> offeringsMap = new HashMap<Long, ServiceOfferingVO>();
-        for (ServiceOfferingVO offering : offerings) {
-            offeringsMap.put(offering.getId(), offering);
+    protected Pair<String, String> getClusterValues(long clusterId) {
+        Map<String, String> map = _clusterDetailsDao.findDetails(clusterId,
+                List.of(VmDetailConstants.CPU_OVER_COMMIT_RATIO, VmDetailConstants.CPU_OVER_COMMIT_RATIO));
+        return new Pair<>(map.get(VmDetailConstants.CPU_OVER_COMMIT_RATIO),
+                map.get(VmDetailConstants.CPU_OVER_COMMIT_RATIO));
+    }
+
+
+    protected Map<Long, ServiceOfferingVO> getServiceOfferingsMap() {
+        List<ServiceOfferingVO> serviceOfferings = _offeringsDao.listAllIncludingRemoved();
+        if (CollectionUtils.isEmpty(serviceOfferings)) {
+            return new HashMap<>();
+        }
+        return serviceOfferings.stream()
+                .collect(Collectors.toMap(
+                        ServiceOfferingVO::getId,
+                        offering -> offering
+                ));
+    }
+
+    protected ServiceOfferingVO getServiceOffering(long id) {
+        Map <Long, ServiceOfferingVO> map = serviceOfferingsCache.get();
+        if (map.containsKey(id)) {
+            return map.get(id);
+        }
+        ServiceOfferingVO serviceOfferingVO = _offeringsDao.findByIdIncludingRemoved(id);
+        if (serviceOfferingVO != null) {
+            serviceOfferingsCache.invalidate();
         }
-        updateCapacityForHost(host, offeringsMap);
+        return serviceOfferingVO;
+    }
+
+    protected Map<String, String> getVmDetailsForCapacityCalculation(long vmId) {
+        return _userVmDetailsDao.listDetailsKeyPairs(vmId,
+                List.of(VmDetailConstants.CPU_OVER_COMMIT_RATIO,
+                        VmDetailConstants.MEMORY_OVER_COMMIT_RATIO,
+                        UsageEventVO.DynamicParameters.memory.name(),
+                        UsageEventVO.DynamicParameters.cpuNumber.name(),
+                        UsageEventVO.DynamicParameters.cpuSpeed.name()));
     }
 
     @DB
     @Override
-    public void updateCapacityForHost(final Host host, final Map<Long, ServiceOfferingVO> offeringsMap) {
+    public void updateCapacityForHost(final Host host) {
         long usedCpuCore = 0;
         long reservedCpuCore = 0;
         long usedCpu = 0;
@@ -653,32 +684,27 @@ public void updateCapacityForHost(final Host host, final Map<Long, ServiceOfferi
         long reservedCpu = 0;
         final CapacityState capacityState = (host.getResourceState() == ResourceState.Enabled) ? CapacityState.Enabled : CapacityState.Disabled;
 
-        List<VMInstanceVO> vms = _vmDao.listUpByHostId(host.getId());
-        if (logger.isDebugEnabled()) {
-            logger.debug("Found " + vms.size() + " VMs on host " + host.getId());
-        }
+        List<VMInstanceVO> vms = _vmDao.listIdServiceOfferingForUpVmsByHostId(host.getId());
+        logger.debug("Found {} VMs on host {}", vms.size(), host.getId());
 
-        final List<VMInstanceVO> vosMigrating = _vmDao.listVmsMigratingFromHost(host.getId());
-        if (logger.isDebugEnabled()) {
-            logger.debug("Found " + vosMigrating.size() + " VMs are Migrating from host " + host.getId());
-        }
+        final List<VMInstanceVO> vosMigrating = _vmDao.listIdServiceOfferingForVmsMigratingFromHost(host.getId());
+        logger.debug("Found {} VMs are Migrating from host {}", vosMigrating.size(), host.getId());
         vms.addAll(vosMigrating);
 
-        ClusterVO cluster = _clusterDao.findById(host.getClusterId());
-        ClusterDetailsVO clusterDetailCpu = _clusterDetailsDao.findDetail(cluster.getId(), "cpuOvercommitRatio");
-        ClusterDetailsVO clusterDetailRam = _clusterDetailsDao.findDetail(cluster.getId(), "memoryOvercommitRatio");
-        Float clusterCpuOvercommitRatio = Float.parseFloat(clusterDetailCpu.getValue());
-        Float clusterRamOvercommitRatio = Float.parseFloat(clusterDetailRam.getValue());
+        Pair<String, String> clusterValues =
+                clusterValuesCache.get(host.getClusterId());
+        Float clusterCpuOvercommitRatio = Float.parseFloat(clusterValues.first());
+        Float clusterRamOvercommitRatio = Float.parseFloat(clusterValues.second());
         for (VMInstanceVO vm : vms) {
             Float cpuOvercommitRatio = 1.0f;
             Float ramOvercommitRatio = 1.0f;
-            Map<String, String> vmDetails = _userVmDetailsDao.listDetailsKeyPairs(vm.getId());
-            String vmDetailCpu = vmDetails.get("cpuOvercommitRatio");
-            String vmDetailRam = vmDetails.get("memoryOvercommitRatio");
+            Map<String, String> vmDetails = getVmDetailsForCapacityCalculation(vm.getId());
+            String vmDetailCpu = vmDetails.get(VmDetailConstants.CPU_OVER_COMMIT_RATIO);
+            String vmDetailRam = vmDetails.get(VmDetailConstants.MEMORY_OVER_COMMIT_RATIO);
             // if vmDetailCpu or vmDetailRam is not null it means it is running in a overcommitted cluster.
             cpuOvercommitRatio = (vmDetailCpu != null) ? Float.parseFloat(vmDetailCpu) : clusterCpuOvercommitRatio;
             ramOvercommitRatio = (vmDetailRam != null) ? Float.parseFloat(vmDetailRam) : clusterRamOvercommitRatio;
-            ServiceOffering so = offeringsMap.get(vm.getServiceOfferingId());
+            ServiceOffering so = getServiceOffering(vm.getServiceOfferingId());
             if (so == null) {
                 so = _offeringsDao.findByIdIncludingRemoved(vm.getServiceOfferingId());
             }
@@ -703,27 +729,26 @@ public void updateCapacityForHost(final Host host, final Map<Long, ServiceOfferi
             }
         }
 
-        List<VMInstanceVO> vmsByLastHostId = _vmDao.listByLastHostId(host.getId());
-        if (logger.isDebugEnabled()) {
-            logger.debug("Found " + vmsByLastHostId.size() + " VM, not running on host " + host.getId());
-        }
+        List<VMInstanceVO> vmsByLastHostId = _vmDao.listIdServiceOfferingForVmsByLastHostId(host.getId());
+        logger.debug("Found {} VM, not running on host {}", vmsByLastHostId.size(), host.getId());
+
         for (VMInstanceVO vm : vmsByLastHostId) {
             Float cpuOvercommitRatio = 1.0f;
             Float ramOvercommitRatio = 1.0f;
             long lastModificationTime = Optional.ofNullable(vm.getUpdateTime()).orElse(vm.getCreated()).getTime();
             long secondsSinceLastUpdate = (DateUtil.currentGMTTime().getTime() - lastModificationTime) / 1000;
             if (secondsSinceLastUpdate < _vmCapacityReleaseInterval) {
-                UserVmDetailVO vmDetailCpu = _userVmDetailsDao.findDetail(vm.getId(), VmDetailConstants.CPU_OVER_COMMIT_RATIO);
-                UserVmDetailVO vmDetailRam = _userVmDetailsDao.findDetail(vm.getId(), VmDetailConstants.MEMORY_OVER_COMMIT_RATIO);
+                Map<String, String> vmDetails = getVmDetailsForCapacityCalculation(vm.getId());
+                String vmDetailCpu = vmDetails.get(VmDetailConstants.CPU_OVER_COMMIT_RATIO);
+                String vmDetailRam = vmDetails.get(VmDetailConstants.MEMORY_OVER_COMMIT_RATIO);
                 if (vmDetailCpu != null) {
                     //if vmDetail_cpu is not null it means it is running in a overcommited cluster.
-                    cpuOvercommitRatio = Float.parseFloat(vmDetailCpu.getValue());
+                    cpuOvercommitRatio = Float.parseFloat(vmDetailCpu);
                 }
                 if (vmDetailRam != null) {
-                    ramOvercommitRatio = Float.parseFloat(vmDetailRam.getValue());
+                    ramOvercommitRatio = Float.parseFloat(vmDetailRam);
                 }
-                ServiceOffering so = offeringsMap.get(vm.getServiceOfferingId());
-                Map<String, String> vmDetails = _userVmDetailsDao.listDetailsKeyPairs(vm.getId());
+                ServiceOffering so = getServiceOffering(vm.getServiceOfferingId());
                 if (so == null) {
                     so = _offeringsDao.findByIdIncludingRemoved(vm.getServiceOfferingId());
                 }
@@ -763,9 +788,24 @@ public void updateCapacityForHost(final Host host, final Map<Long, ServiceOfferi
             }
         }
 
-        CapacityVO cpuCap = _capacityDao.findByHostIdType(host.getId(), Capacity.CAPACITY_TYPE_CPU);
-        CapacityVO memCap = _capacityDao.findByHostIdType(host.getId(), Capacity.CAPACITY_TYPE_MEMORY);
-        CapacityVO cpuCoreCap = _capacityDao.findByHostIdType(host.getId(), CapacityVO.CAPACITY_TYPE_CPU_CORE);
+        List<CapacityVO> capacities = _capacityDao.listByHostIdTypes(host.getId(), List.of(Capacity.CAPACITY_TYPE_CPU,
+                Capacity.CAPACITY_TYPE_MEMORY,
+                CapacityVO.CAPACITY_TYPE_CPU_CORE));
+        CapacityVO cpuCap = null;
+        CapacityVO memCap = null;
+        CapacityVO cpuCoreCap = null;
+        for (CapacityVO c : capacities) {
+            if (c.getCapacityType() == Capacity.CAPACITY_TYPE_CPU) {
+                cpuCap = c;
+            } else if (c.getCapacityType() == Capacity.CAPACITY_TYPE_MEMORY) {
+                memCap = c;
+            } else if (c.getCapacityType() == Capacity.CAPACITY_TYPE_CPU_CORE) {
+                cpuCoreCap = c;
+            }
+            if (ObjectUtils.allNotNull(cpuCap, memCap, cpuCoreCap)) {
+                break;
+            }
+        }
 
         if (cpuCoreCap != null) {
             long hostTotalCpuCore = host.getCpus().longValue();
@@ -1006,8 +1046,8 @@ private void createCapacityEntry(StartupCommand startup, HostVO server) {
             capacityCPU.addAnd("podId", SearchCriteria.Op.EQ, server.getPodId());
             capacityCPU.addAnd("capacityType", SearchCriteria.Op.EQ, Capacity.CAPACITY_TYPE_CPU);
             List<CapacityVO> capacityVOCpus = _capacityDao.search(capacitySC, null);
-            Float cpuovercommitratio = Float.parseFloat(_clusterDetailsDao.findDetail(server.getClusterId(), "cpuOvercommitRatio").getValue());
-            Float memoryOvercommitRatio = Float.parseFloat(_clusterDetailsDao.findDetail(server.getClusterId(), "memoryOvercommitRatio").getValue());
+            Float cpuovercommitratio = Float.parseFloat(_clusterDetailsDao.findDetail(server.getClusterId(), VmDetailConstants.CPU_OVER_COMMIT_RATIO).getValue());
+            Float memoryOvercommitRatio = Float.parseFloat(_clusterDetailsDao.findDetail(server.getClusterId(), VmDetailConstants.MEMORY_OVER_COMMIT_RATIO).getValue());
 
             if (capacityVOCpus != null && !capacityVOCpus.isEmpty()) {
                 CapacityVO CapacityVOCpu = capacityVOCpus.get(0);
@@ -1064,9 +1104,9 @@ public float getClusterOverProvisioningFactor(Long clusterId, short capacityType
 
         String capacityOverProvisioningName = "";
         if (capacityType == Capacity.CAPACITY_TYPE_CPU) {
-            capacityOverProvisioningName = "cpuOvercommitRatio";
+            capacityOverProvisioningName = VmDetailConstants.CPU_OVER_COMMIT_RATIO;
         } else if (capacityType == Capacity.CAPACITY_TYPE_MEMORY) {
-            capacityOverProvisioningName = "memoryOvercommitRatio";
+            capacityOverProvisioningName = VmDetailConstants.MEMORY_OVER_COMMIT_RATIO;
         } else {
             throw new CloudRuntimeException("Invalid capacityType - " + capacityType);
         }
@@ -1108,12 +1148,12 @@ public Pair<Boolean, Boolean> checkIfHostHasCpuCapabilityAndCapacity(Host host,
         int cpu_requested = offering.getCpu() * offering.getSpeed();
         long ram_requested = offering.getRamSize() * 1024L * 1024L;
         Cluster cluster = _clusterDao.findById(host.getClusterId());
-        ClusterDetailsVO clusterDetailsCpuOvercommit = _clusterDetailsDao.findDetail(cluster.getId(), "cpuOvercommitRatio");
-        ClusterDetailsVO clusterDetailsRamOvercommmt = _clusterDetailsDao.findDetail(cluster.getId(), "memoryOvercommitRatio");
+        ClusterDetailsVO clusterDetailsCpuOvercommit = _clusterDetailsDao.findDetail(cluster.getId(), VmDetailConstants.CPU_OVER_COMMIT_RATIO);
+        ClusterDetailsVO clusterDetailsRamOvercommmt = _clusterDetailsDao.findDetail(cluster.getId(), VmDetailConstants.MEMORY_OVER_COMMIT_RATIO);
         Float cpuOvercommitRatio = Float.parseFloat(clusterDetailsCpuOvercommit.getValue());
         Float memoryOvercommitRatio = Float.parseFloat(clusterDetailsRamOvercommmt.getValue());
 
-        boolean hostHasCpuCapability = checkIfHostHasCpuCapability(host.getId(), offering.getCpu(), offering.getSpeed());
+        boolean hostHasCpuCapability = checkIfHostHasCpuCapability(host, offering.getCpu(), offering.getSpeed());
         boolean hostHasCapacity = checkIfHostHasCapacity(host.getId(), cpu_requested, ram_requested, false, cpuOvercommitRatio, memoryOvercommitRatio,
                 considerReservedCapacity);
 
@@ -1254,6 +1294,7 @@ public String getConfigComponentName() {
     @Override
     public ConfigKey<?>[] getConfigKeys() {
         return new ConfigKey<?>[] {CpuOverprovisioningFactor, MemOverprovisioningFactor, StorageCapacityDisableThreshold, StorageOverprovisioningFactor,
-            StorageAllocatedCapacityDisableThreshold, StorageOperationsExcludeCluster, ImageStoreNFSVersion, SecondaryStorageCapacityThreshold};
+            StorageAllocatedCapacityDisableThreshold, StorageOperationsExcludeCluster, ImageStoreNFSVersion, SecondaryStorageCapacityThreshold,
+            CapacityCalculateWorkers };
     }
 }
diff --git a/server/src/main/java/com/cloud/configuration/ConfigurationManagerImpl.java b/server/src/main/java/com/cloud/configuration/ConfigurationManagerImpl.java
index 25cbd10de0a4..7825ff9a684e 100644
--- a/server/src/main/java/com/cloud/configuration/ConfigurationManagerImpl.java
+++ b/server/src/main/java/com/cloud/configuration/ConfigurationManagerImpl.java
@@ -16,6 +16,10 @@
 // under the License.
 package com.cloud.configuration;
 
+import static com.cloud.configuration.Config.SecStorageAllowedInternalDownloadSites;
+import static com.cloud.offering.NetworkOffering.RoutingMode.Dynamic;
+import static com.cloud.offering.NetworkOffering.RoutingMode.Static;
+
 import java.io.UnsupportedEncodingException;
 import java.net.URI;
 import java.net.URISyntaxException;
@@ -306,10 +310,6 @@
 import com.googlecode.ipv6.IPv6Address;
 import com.googlecode.ipv6.IPv6Network;
 
-import static com.cloud.configuration.Config.SecStorageAllowedInternalDownloadSites;
-import static com.cloud.offering.NetworkOffering.RoutingMode.Dynamic;
-import static com.cloud.offering.NetworkOffering.RoutingMode.Static;
-
 public class ConfigurationManagerImpl extends ManagerBase implements ConfigurationManager, ConfigurationService, Configurable {
     public static final String PERACCOUNT = "peraccount";
     public static final String PERZONE = "perzone";
@@ -2428,7 +2428,7 @@ protected void checkIfZoneIsDeletable(final long zoneId) {
 
 
         // Check if there are any non-removed hosts in the zone.
-        if (!_hostDao.listByDataCenterId(zoneId).isEmpty()) {
+        if (!_hostDao.listEnabledIdsByDataCenterId(zoneId).isEmpty()) {
             throw new CloudRuntimeException(errorMsg + "there are servers in this zone.");
         }
 
diff --git a/server/src/main/java/com/cloud/consoleproxy/ConsoleProxyManagerImpl.java b/server/src/main/java/com/cloud/consoleproxy/ConsoleProxyManagerImpl.java
index 53f76f8ad420..9311ee9c8705 100644
--- a/server/src/main/java/com/cloud/consoleproxy/ConsoleProxyManagerImpl.java
+++ b/server/src/main/java/com/cloud/consoleproxy/ConsoleProxyManagerImpl.java
@@ -873,10 +873,10 @@ private void allocCapacity(long dataCenterId) {
     }
 
     public boolean isZoneReady(Map<Long, ZoneHostInfo> zoneHostInfoMap, long dataCenterId) {
-        List <HostVO> hosts = hostDao.listByDataCenterId(dataCenterId);
-        if (CollectionUtils.isEmpty(hosts)) {
+        Integer totalUpAndEnabledHosts = hostDao.countUpAndEnabledHostsInZone(dataCenterId);
+        if (totalUpAndEnabledHosts != null && totalUpAndEnabledHosts < 1) {
             if (logger.isDebugEnabled()) {
-                logger.debug("Zone " + dataCenterId + " has no host available which is enabled and in Up state");
+                logger.debug("Zone {} has no host available which is enabled and in Up state", dataCenterId);
             }
             return false;
         }
@@ -898,8 +898,8 @@ public boolean isZoneReady(Map<Long, ZoneHostInfo> zoneHostInfoMap, long dataCen
 
             if (templateHostRef != null) {
                 Boolean useLocalStorage = BooleanUtils.toBoolean(ConfigurationManagerImpl.SystemVMUseLocalStorage.valueIn(dataCenterId));
-                List<Pair<Long, Integer>> l = consoleProxyDao.getDatacenterStoragePoolHostInfo(dataCenterId, useLocalStorage);
-                if (CollectionUtils.isNotEmpty(l) && l.get(0).second() > 0) {
+                boolean hasDatacenterStoragePoolHostInfo = consoleProxyDao.hasDatacenterStoragePoolHostInfo(dataCenterId, !useLocalStorage);
+                if (hasDatacenterStoragePoolHostInfo) {
                     return true;
                 } else {
                     if (logger.isDebugEnabled()) {
diff --git a/server/src/main/java/com/cloud/deploy/DeploymentPlanningManagerImpl.java b/server/src/main/java/com/cloud/deploy/DeploymentPlanningManagerImpl.java
index 19760e6d0251..9d4ebf04fb73 100644
--- a/server/src/main/java/com/cloud/deploy/DeploymentPlanningManagerImpl.java
+++ b/server/src/main/java/com/cloud/deploy/DeploymentPlanningManagerImpl.java
@@ -36,23 +36,7 @@
 import javax.inject.Inject;
 import javax.naming.ConfigurationException;
 
-import com.cloud.cpu.CPU;
-import com.cloud.vm.UserVmManager;
 import org.apache.cloudstack.affinity.AffinityGroupDomainMapVO;
-import com.cloud.storage.VMTemplateVO;
-import com.cloud.storage.dao.VMTemplateDao;
-import com.cloud.user.AccountVO;
-import com.cloud.user.dao.AccountDao;
-import com.cloud.exception.StorageUnavailableException;
-import com.cloud.utils.db.Filter;
-import com.cloud.utils.fsm.StateMachine2;
-
-import org.apache.cloudstack.framework.config.ConfigKey;
-import org.apache.cloudstack.framework.config.Configurable;
-import org.apache.cloudstack.utils.reflectiontostringbuilderutils.ReflectionToStringBuilderUtils;
-import org.apache.commons.collections.CollectionUtils;
-import org.apache.commons.collections.MapUtils;
-import org.apache.commons.lang3.StringUtils;
 import org.apache.cloudstack.affinity.AffinityGroupProcessor;
 import org.apache.cloudstack.affinity.AffinityGroupService;
 import org.apache.cloudstack.affinity.AffinityGroupVMMapVO;
@@ -65,6 +49,8 @@
 import org.apache.cloudstack.engine.subsystem.api.storage.DataStore;
 import org.apache.cloudstack.engine.subsystem.api.storage.DataStoreManager;
 import org.apache.cloudstack.engine.subsystem.api.storage.StoragePoolAllocator;
+import org.apache.cloudstack.framework.config.ConfigKey;
+import org.apache.cloudstack.framework.config.Configurable;
 import org.apache.cloudstack.framework.config.dao.ConfigurationDao;
 import org.apache.cloudstack.framework.messagebus.MessageBus;
 import org.apache.cloudstack.framework.messagebus.MessageSubscriber;
@@ -72,6 +58,10 @@
 import org.apache.cloudstack.storage.datastore.db.PrimaryDataStoreDao;
 import org.apache.cloudstack.storage.datastore.db.StoragePoolVO;
 import org.apache.cloudstack.utils.identity.ManagementServerNode;
+import org.apache.cloudstack.utils.reflectiontostringbuilderutils.ReflectionToStringBuilderUtils;
+import org.apache.commons.collections.CollectionUtils;
+import org.apache.commons.collections.MapUtils;
+import org.apache.commons.lang3.StringUtils;
 
 import com.cloud.agent.AgentManager;
 import com.cloud.agent.Listener;
@@ -86,6 +76,7 @@
 import com.cloud.capacity.dao.CapacityDao;
 import com.cloud.configuration.Config;
 import com.cloud.configuration.ConfigurationManagerImpl;
+import com.cloud.cpu.CPU;
 import com.cloud.dc.ClusterDetailsDao;
 import com.cloud.dc.ClusterDetailsVO;
 import com.cloud.dc.ClusterVO;
@@ -103,6 +94,7 @@
 import com.cloud.exception.AffinityConflictException;
 import com.cloud.exception.ConnectionException;
 import com.cloud.exception.InsufficientServerCapacityException;
+import com.cloud.exception.StorageUnavailableException;
 import com.cloud.gpu.GPU;
 import com.cloud.host.DetailVO;
 import com.cloud.host.Host;
@@ -123,15 +115,19 @@
 import com.cloud.storage.StorageManager;
 import com.cloud.storage.StoragePool;
 import com.cloud.storage.StoragePoolHostVO;
+import com.cloud.storage.VMTemplateVO;
 import com.cloud.storage.Volume;
 import com.cloud.storage.VolumeVO;
 import com.cloud.storage.dao.DiskOfferingDao;
 import com.cloud.storage.dao.GuestOSCategoryDao;
 import com.cloud.storage.dao.GuestOSDao;
 import com.cloud.storage.dao.StoragePoolHostDao;
+import com.cloud.storage.dao.VMTemplateDao;
 import com.cloud.storage.dao.VolumeDao;
 import com.cloud.template.VirtualMachineTemplate;
 import com.cloud.user.AccountManager;
+import com.cloud.user.AccountVO;
+import com.cloud.user.dao.AccountDao;
 import com.cloud.utils.DateUtil;
 import com.cloud.utils.LogUtils;
 import com.cloud.utils.NumbersUtil;
@@ -139,13 +135,16 @@
 import com.cloud.utils.component.Manager;
 import com.cloud.utils.component.ManagerBase;
 import com.cloud.utils.db.DB;
+import com.cloud.utils.db.Filter;
 import com.cloud.utils.db.SearchCriteria;
 import com.cloud.utils.db.Transaction;
 import com.cloud.utils.db.TransactionCallback;
 import com.cloud.utils.db.TransactionStatus;
 import com.cloud.utils.exception.CloudRuntimeException;
 import com.cloud.utils.fsm.StateListener;
+import com.cloud.utils.fsm.StateMachine2;
 import com.cloud.vm.DiskProfile;
+import com.cloud.vm.UserVmManager;
 import com.cloud.vm.VMInstanceVO;
 import com.cloud.vm.VirtualMachine;
 import com.cloud.vm.VirtualMachine.Event;
@@ -298,7 +297,7 @@ protected void avoidOtherClustersForDeploymentIfMigrationDisabled(VirtualMachine
         final Long lastHostClusterId = lastHost.getClusterId();
         logger.warn(String.format("VM last host ID: %d belongs to zone ID: %s for which config - %s is false and storage migration would be needed for inter-cluster migration, therefore, adding all other clusters except ID: %d from this zone to avoid list",
                 lastHost.getId(), vm.getDataCenterId(), ConfigurationManagerImpl.MIGRATE_VM_ACROSS_CLUSTERS.key(), lastHostClusterId));
-        List<Long> clusterIds = _clusterDao.listAllClusters(lastHost.getDataCenterId());
+        List<Long> clusterIds = _clusterDao.listAllClusterIds(lastHost.getDataCenterId());
         Set<Long> existingAvoidedClusters = avoids.getClustersToAvoid();
         clusterIds = clusterIds.stream().filter(x -> !Objects.equals(x, lastHostClusterId) && (existingAvoidedClusters == null || !existingAvoidedClusters.contains(x))).collect(Collectors.toList());
         avoids.addClusterList(clusterIds);
@@ -496,7 +495,7 @@ private DeployDestination deployInVmLastHost(VirtualMachineProfile vmProfile, De
                 float memoryOvercommitRatio = Float.parseFloat(cluster_detail_ram.getValue());
 
                 boolean hostHasCpuCapability, hostHasCapacity = false;
-                hostHasCpuCapability = _capacityMgr.checkIfHostHasCpuCapability(host.getId(), offering.getCpu(), offering.getSpeed());
+                hostHasCpuCapability = _capacityMgr.checkIfHostHasCpuCapability(host, offering.getCpu(), offering.getSpeed());
 
                 if (hostHasCpuCapability) {
                     // first check from reserved capacity
@@ -742,12 +741,11 @@ protected boolean isAdminVmDeployableInDisabledResources() {
      * Adds disabled Hosts to the ExcludeList in order to avoid them at the deployment planner.
      */
     protected void avoidDisabledHosts(DataCenter dc, ExcludeList avoids) {
-        List<HostVO> disabledHosts = _hostDao.listDisabledByDataCenterId(dc.getId());
-        logger.debug(() -> String.format("Adding hosts [%s] of datacenter [%s] to the avoid set, because these hosts are in the Disabled state.",
-                disabledHosts.stream().map(HostVO::getUuid).collect(Collectors.joining(", ")), dc.getUuid()));
-        for (HostVO host : disabledHosts) {
-            avoids.addHost(host.getId());
-        }
+
+        List<Long> disabledHostIds = _hostDao.listDisabledIdsByDataCenterId(dc.getId());
+        logger.debug("Adding hosts %s of datacenter [%s] to the avoid set, because these hosts are in the Disabled state.",
+                StringUtils.join(disabledHostIds), dc.getUuid());
+        disabledHostIds.forEach(avoids::addHost);
     }
 
     /**
@@ -865,7 +863,7 @@ public void checkForNonDedicatedResources(VirtualMachineProfile vmProfile, DataC
         List<Long> allDedicatedPods = _dedicatedDao.listAllPods();
         allPodsInDc.retainAll(allDedicatedPods);
 
-        List<Long> allClustersInDc = _clusterDao.listAllClusters(dc.getId());
+        List<Long> allClustersInDc = _clusterDao.listAllClusterIds(dc.getId());
         List<Long> allDedicatedClusters = _dedicatedDao.listAllClusters();
         allClustersInDc.retainAll(allDedicatedClusters);
 
@@ -1152,11 +1150,13 @@ protected void runInContext() {
 
     private void checkHostReservations() {
         List<PlannerHostReservationVO> reservedHosts = _plannerHostReserveDao.listAllReservedHosts();
-
-        for (PlannerHostReservationVO hostReservation : reservedHosts) {
-            HostVO host = _hostDao.findById(hostReservation.getHostId());
+        List<HostVO> hosts = _hostDao.listByIds(reservedHosts
+                .stream()
+                .map(PlannerHostReservationVO::getHostId)
+                .collect(Collectors.toList()));
+        for (HostVO host : hosts) {
             if (host != null && host.getManagementServerId() != null && host.getManagementServerId() == _nodeId) {
-                checkHostReservationRelease(hostReservation.getHostId());
+                checkHostReservationRelease(host.getId());
             }
         }
 
@@ -1344,7 +1344,7 @@ private DeployDestination checkClustersforDestination(List<Long> clusterList, Vi
                         Pair<Host, Map<Volume, StoragePool>> potentialResources = findPotentialDeploymentResources(suitableHosts, suitableVolumeStoragePools, avoid,
                                 resourceUsageRequired, readyAndReusedVolumes, plan.getPreferredHosts(), vmProfile.getVirtualMachine());
                         if (potentialResources != null) {
-                            Host host = _hostDao.findById(potentialResources.first().getId());
+                            Host host = potentialResources.first();
                             Map<Volume, StoragePool> storageVolMap = potentialResources.second();
                             // remove the reused vol<->pool from destination, since
                             // we don't have to prepare this volume.
diff --git a/server/src/main/java/com/cloud/hypervisor/kvm/discoverer/LibvirtServerDiscoverer.java b/server/src/main/java/com/cloud/hypervisor/kvm/discoverer/LibvirtServerDiscoverer.java
index ffd482b711d6..4209b0d23261 100644
--- a/server/src/main/java/com/cloud/hypervisor/kvm/discoverer/LibvirtServerDiscoverer.java
+++ b/server/src/main/java/com/cloud/hypervisor/kvm/discoverer/LibvirtServerDiscoverer.java
@@ -16,6 +16,29 @@
 // under the License.
 package com.cloud.hypervisor.kvm.discoverer;
 
+import static com.cloud.configuration.ConfigurationManagerImpl.ADD_HOST_ON_SERVICE_RESTART_KVM;
+
+import java.net.InetAddress;
+import java.net.URI;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.UUID;
+
+import javax.inject.Inject;
+import javax.naming.ConfigurationException;
+
+import org.apache.cloudstack.agent.lb.IndirectAgentLB;
+import org.apache.cloudstack.ca.CAManager;
+import org.apache.cloudstack.ca.SetupCertificateCommand;
+import org.apache.cloudstack.direct.download.DirectDownloadManager;
+import org.apache.cloudstack.framework.ca.Certificate;
+import org.apache.cloudstack.utils.cache.LazyCache;
+import org.apache.cloudstack.utils.security.KeyStoreUtils;
+
 import com.cloud.agent.AgentManager;
 import com.cloud.agent.Listener;
 import com.cloud.agent.api.AgentControlAnswer;
@@ -48,26 +71,7 @@
 import com.cloud.utils.exception.CloudRuntimeException;
 import com.cloud.utils.ssh.SSHCmdHelper;
 import com.trilead.ssh2.Connection;
-import org.apache.cloudstack.agent.lb.IndirectAgentLB;
-import org.apache.cloudstack.ca.CAManager;
-import org.apache.cloudstack.ca.SetupCertificateCommand;
-import org.apache.cloudstack.direct.download.DirectDownloadManager;
-import org.apache.cloudstack.framework.ca.Certificate;
-import org.apache.cloudstack.utils.security.KeyStoreUtils;
 
-import javax.inject.Inject;
-import javax.naming.ConfigurationException;
-import java.net.InetAddress;
-import java.net.URI;
-import java.util.Arrays;
-import java.util.Collections;
-import java.util.HashMap;
-import java.util.HashSet;
-import java.util.List;
-import java.util.Map;
-import java.util.UUID;
-
-import static com.cloud.configuration.ConfigurationManagerImpl.ADD_HOST_ON_SERVICE_RESTART_KVM;
 
 public abstract class LibvirtServerDiscoverer extends DiscovererBase implements Discoverer, Listener, ResourceStateAdapter {
     private final int _waitTime = 5; /* wait for 5 minutes */
@@ -89,6 +93,16 @@ public abstract class LibvirtServerDiscoverer extends DiscovererBase implements
     @Inject
     private HostDao hostDao;
 
+    private LazyCache<Long, HostVO> clusterExistingHostCache;
+
+    private HostVO getExistingHostForCluster(long clusterId) {
+        HostVO existingHostInCluster = _hostDao.findAnyStateHypervisorHostInCluster(clusterId);
+        if (existingHostInCluster != null) {
+            _hostDao.loadDetails(existingHostInCluster);
+        }
+        return existingHostInCluster;
+    }
+
     @Override
     public abstract Hypervisor.HypervisorType getHypervisorType();
 
@@ -425,6 +439,9 @@ public boolean configure(String name, Map<String, Object> params) throws Configu
             _kvmGuestNic = _kvmPrivateNic;
         }
 
+        clusterExistingHostCache = new LazyCache<>(32, 30,
+                this::getExistingHostForCluster);
+
         agentMgr.registerForHostEvents(this, true, false, false);
         _resourceMgr.registerResourceStateAdapter(this.getClass().getSimpleName(), this);
         return true;
@@ -467,11 +484,9 @@ public HostVO createHostVOForConnectedAgent(HostVO host, StartupCommand[] cmd) {
             throw new IllegalArgumentException("cannot add host, due to can't find cluster: " + host.getClusterId());
         }
 
-        List<HostVO> hostsInCluster = _resourceMgr.listAllHostsInCluster(clusterVO.getId());
-        if (!hostsInCluster.isEmpty()) {
-            HostVO oneHost = hostsInCluster.get(0);
-            _hostDao.loadDetails(oneHost);
-            String hostOsInCluster = oneHost.getDetail("Host.OS");
+        HostVO existingHostInCluster = clusterExistingHostCache.get(clusterVO.getId());
+        if (existingHostInCluster != null) {
+            String hostOsInCluster = existingHostInCluster.getDetail("Host.OS");
             String hostOs = ssCmd.getHostDetails().get("Host.OS");
             if (!isHostOsCompatibleWithOtherHost(hostOsInCluster, hostOs)) {
                 String msg = String.format("host: %s with hostOS, \"%s\"into a cluster, in which there are \"%s\" hosts added", firstCmd.getPrivateIpAddress(), hostOs, hostOsInCluster);
diff --git a/server/src/main/java/com/cloud/network/NetworkServiceImpl.java b/server/src/main/java/com/cloud/network/NetworkServiceImpl.java
index 2ccd5fdd8202..8b3e23572380 100644
--- a/server/src/main/java/com/cloud/network/NetworkServiceImpl.java
+++ b/server/src/main/java/com/cloud/network/NetworkServiceImpl.java
@@ -40,16 +40,6 @@
 import javax.inject.Inject;
 import javax.naming.ConfigurationException;
 
-import com.cloud.bgp.BGPService;
-import com.cloud.dc.VlanDetailsVO;
-import com.cloud.dc.dao.VlanDetailsDao;
-import com.cloud.network.dao.NsxProviderDao;
-import com.cloud.network.dao.PublicIpQuarantineDao;
-import com.cloud.network.dao.VirtualRouterProviderDao;
-import com.cloud.network.element.NsxProviderVO;
-import com.cloud.network.element.VirtualRouterProviderVO;
-import com.cloud.offering.ServiceOffering;
-import com.cloud.service.dao.ServiceOfferingDao;
 import org.apache.cloudstack.acl.ControlledEntity.ACLType;
 import org.apache.cloudstack.acl.SecurityChecker.AccessType;
 import org.apache.cloudstack.alert.AlertService;
@@ -104,6 +94,7 @@
 import com.cloud.api.ApiDBUtils;
 import com.cloud.api.query.dao.DomainRouterJoinDao;
 import com.cloud.api.query.vo.DomainRouterJoinVO;
+import com.cloud.bgp.BGPService;
 import com.cloud.configuration.Config;
 import com.cloud.configuration.ConfigurationManager;
 import com.cloud.configuration.Resource;
@@ -114,12 +105,14 @@
 import com.cloud.dc.DataCenterVnetVO;
 import com.cloud.dc.DomainVlanMapVO;
 import com.cloud.dc.Vlan.VlanType;
+import com.cloud.dc.VlanDetailsVO;
 import com.cloud.dc.VlanVO;
 import com.cloud.dc.dao.AccountVlanMapDao;
 import com.cloud.dc.dao.DataCenterDao;
 import com.cloud.dc.dao.DataCenterVnetDao;
 import com.cloud.dc.dao.DomainVlanMapDao;
 import com.cloud.dc.dao.VlanDao;
+import com.cloud.dc.dao.VlanDetailsDao;
 import com.cloud.deploy.DeployDestination;
 import com.cloud.domain.Domain;
 import com.cloud.domain.DomainVO;
@@ -165,6 +158,7 @@
 import com.cloud.network.dao.NetworkDomainVO;
 import com.cloud.network.dao.NetworkServiceMapDao;
 import com.cloud.network.dao.NetworkVO;
+import com.cloud.network.dao.NsxProviderDao;
 import com.cloud.network.dao.OvsProviderDao;
 import com.cloud.network.dao.PhysicalNetworkDao;
 import com.cloud.network.dao.PhysicalNetworkServiceProviderDao;
@@ -172,9 +166,13 @@
 import com.cloud.network.dao.PhysicalNetworkTrafficTypeDao;
 import com.cloud.network.dao.PhysicalNetworkTrafficTypeVO;
 import com.cloud.network.dao.PhysicalNetworkVO;
+import com.cloud.network.dao.PublicIpQuarantineDao;
+import com.cloud.network.dao.VirtualRouterProviderDao;
 import com.cloud.network.element.NetworkElement;
+import com.cloud.network.element.NsxProviderVO;
 import com.cloud.network.element.OvsProviderVO;
 import com.cloud.network.element.VirtualRouterElement;
+import com.cloud.network.element.VirtualRouterProviderVO;
 import com.cloud.network.element.VpcVirtualRouterElement;
 import com.cloud.network.guru.GuestNetworkGuru;
 import com.cloud.network.guru.NetworkGuru;
@@ -198,6 +196,7 @@
 import com.cloud.network.vpc.dao.VpcGatewayDao;
 import com.cloud.network.vpc.dao.VpcOfferingDao;
 import com.cloud.offering.NetworkOffering;
+import com.cloud.offering.ServiceOffering;
 import com.cloud.offerings.NetworkOfferingVO;
 import com.cloud.offerings.dao.NetworkOfferingDao;
 import com.cloud.offerings.dao.NetworkOfferingServiceMapDao;
@@ -207,6 +206,7 @@
 import com.cloud.server.ResourceTag;
 import com.cloud.server.ResourceTag.ResourceObjectType;
 import com.cloud.service.ServiceOfferingVO;
+import com.cloud.service.dao.ServiceOfferingDao;
 import com.cloud.tags.ResourceTagVO;
 import com.cloud.tags.dao.ResourceTagDao;
 import com.cloud.user.Account;
diff --git a/server/src/main/java/com/cloud/network/as/AutoScaleManagerImpl.java b/server/src/main/java/com/cloud/network/as/AutoScaleManagerImpl.java
index 5e7a4a0c4efc..fd6ff18f4c72 100644
--- a/server/src/main/java/com/cloud/network/as/AutoScaleManagerImpl.java
+++ b/server/src/main/java/com/cloud/network/as/AutoScaleManagerImpl.java
@@ -2717,7 +2717,7 @@ protected void getVmStatsFromHosts(AutoScaleVmGroupTO groupTO) {
             return vmStatsById;
         }
         try {
-            vmStatsById = virtualMachineManager.getVirtualMachineStatistics(host.getId(), host.getName(), vmIds);
+            vmStatsById = virtualMachineManager.getVirtualMachineStatistics(host, vmIds);
             if (MapUtils.isEmpty(vmStatsById)) {
                 logger.warn("Got empty result for virtual machine statistics from host: " + host);
             }
diff --git a/server/src/main/java/com/cloud/network/security/SecurityGroupListener.java b/server/src/main/java/com/cloud/network/security/SecurityGroupListener.java
index b925137c4ce8..3147365e8ab6 100644
--- a/server/src/main/java/com/cloud/network/security/SecurityGroupListener.java
+++ b/server/src/main/java/com/cloud/network/security/SecurityGroupListener.java
@@ -22,8 +22,8 @@
 import java.util.Random;
 import java.util.concurrent.ConcurrentHashMap;
 
-import org.apache.logging.log4j.Logger;
 import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
 
 import com.cloud.agent.AgentManager;
 import com.cloud.agent.Listener;
diff --git a/server/src/main/java/com/cloud/resource/ResourceManagerImpl.java b/server/src/main/java/com/cloud/resource/ResourceManagerImpl.java
index 228373896204..08dc94f71b8c 100755
--- a/server/src/main/java/com/cloud/resource/ResourceManagerImpl.java
+++ b/server/src/main/java/com/cloud/resource/ResourceManagerImpl.java
@@ -32,20 +32,12 @@
 import java.util.Locale;
 import java.util.Map;
 import java.util.Random;
+import java.util.Set;
 import java.util.stream.Collectors;
 
 import javax.inject.Inject;
 import javax.naming.ConfigurationException;
 
-import com.cloud.alert.AlertManager;
-import com.cloud.cpu.CPU;
-import com.cloud.exception.StorageConflictException;
-import com.cloud.exception.StorageUnavailableException;
-import com.cloud.host.HostTagVO;
-import com.cloud.storage.Volume;
-import com.cloud.storage.VolumeVO;
-import com.cloud.storage.dao.VolumeDao;
-import com.cloud.hypervisor.HypervisorGuru;
 import org.apache.cloudstack.alert.AlertService;
 import org.apache.cloudstack.annotation.AnnotationService;
 import org.apache.cloudstack.annotation.dao.AnnotationDao;
@@ -92,6 +84,7 @@
 import com.cloud.agent.api.VgpuTypesInfo;
 import com.cloud.agent.api.to.GPUDeviceTO;
 import com.cloud.agent.transport.Request;
+import com.cloud.alert.AlertManager;
 import com.cloud.capacity.Capacity;
 import com.cloud.capacity.CapacityManager;
 import com.cloud.capacity.CapacityState;
@@ -100,6 +93,7 @@
 import com.cloud.cluster.ClusterManager;
 import com.cloud.configuration.Config;
 import com.cloud.configuration.ConfigurationManager;
+import com.cloud.cpu.CPU;
 import com.cloud.dc.ClusterDetailsDao;
 import com.cloud.dc.ClusterDetailsVO;
 import com.cloud.dc.ClusterVO;
@@ -133,6 +127,8 @@
 import com.cloud.exception.PermissionDeniedException;
 import com.cloud.exception.ResourceInUseException;
 import com.cloud.exception.ResourceUnavailableException;
+import com.cloud.exception.StorageConflictException;
+import com.cloud.exception.StorageUnavailableException;
 import com.cloud.gpu.GPU;
 import com.cloud.gpu.HostGpuGroupsVO;
 import com.cloud.gpu.VGPUTypesVO;
@@ -144,6 +140,7 @@
 import com.cloud.host.Host;
 import com.cloud.host.Host.Type;
 import com.cloud.host.HostStats;
+import com.cloud.host.HostTagVO;
 import com.cloud.host.HostVO;
 import com.cloud.host.Status;
 import com.cloud.host.Status.Event;
@@ -152,6 +149,7 @@
 import com.cloud.host.dao.HostTagsDao;
 import com.cloud.hypervisor.Hypervisor;
 import com.cloud.hypervisor.Hypervisor.HypervisorType;
+import com.cloud.hypervisor.HypervisorGuru;
 import com.cloud.hypervisor.kvm.discoverer.KvmDummyResourceBase;
 import com.cloud.network.dao.IPAddressDao;
 import com.cloud.network.dao.IPAddressVO;
@@ -169,10 +167,13 @@
 import com.cloud.storage.StoragePoolStatus;
 import com.cloud.storage.StorageService;
 import com.cloud.storage.VMTemplateVO;
+import com.cloud.storage.Volume;
+import com.cloud.storage.VolumeVO;
 import com.cloud.storage.dao.DiskOfferingDao;
 import com.cloud.storage.dao.GuestOSCategoryDao;
 import com.cloud.storage.dao.StoragePoolHostDao;
 import com.cloud.storage.dao.VMTemplateDao;
+import com.cloud.storage.dao.VolumeDao;
 import com.cloud.user.Account;
 import com.cloud.user.AccountManager;
 import com.cloud.utils.Ternary;
@@ -549,8 +550,8 @@ public List<? extends Cluster> discoverCluster(final AddClusterCmd cmd) throws I
                 details.put("ovm3pool", allParams.get("ovm3pool"));
                 details.put("ovm3cluster", allParams.get("ovm3cluster"));
             }
-            details.put("cpuOvercommitRatio", CapacityManager.CpuOverprovisioningFactor.value().toString());
-            details.put("memoryOvercommitRatio", CapacityManager.MemOverprovisioningFactor.value().toString());
+            details.put(VmDetailConstants.CPU_OVER_COMMIT_RATIO, CapacityManager.CpuOverprovisioningFactor.value().toString());
+            details.put(VmDetailConstants.MEMORY_OVER_COMMIT_RATIO, CapacityManager.MemOverprovisioningFactor.value().toString());
             _clusterDetailsDao.persist(cluster.getId(), details);
             return result;
         }
@@ -560,8 +561,8 @@ public List<? extends Cluster> discoverCluster(final AddClusterCmd cmd) throws I
         details.put("url", url);
         details.put("username", StringUtils.defaultString(username));
         details.put("password", StringUtils.defaultString(password));
-        details.put("cpuOvercommitRatio", CapacityManager.CpuOverprovisioningFactor.value().toString());
-        details.put("memoryOvercommitRatio", CapacityManager.MemOverprovisioningFactor.value().toString());
+        details.put(VmDetailConstants.CPU_OVER_COMMIT_RATIO, CapacityManager.CpuOverprovisioningFactor.value().toString());
+        details.put(VmDetailConstants.MEMORY_OVER_COMMIT_RATIO, CapacityManager.MemOverprovisioningFactor.value().toString());
         _clusterDetailsDao.persist(cluster.getId(), details);
 
         boolean success = false;
@@ -645,8 +646,8 @@ public List<? extends Host> discoverHosts(final AddHostCmd cmd) throws IllegalAr
                 throw ex;
             } else {
                 if (cluster.getGuid() == null) {
-                    final List<HostVO> hosts = listAllHostsInCluster(clusterId);
-                    if (!hosts.isEmpty()) {
+                    final List<Long> hostIds = _hostDao.listIdsByClusterId(clusterId);
+                    if (!hostIds.isEmpty()) {
                         final CloudRuntimeException ex =
                                 new CloudRuntimeException("Guid is not updated for cluster with specified cluster id; need to wait for hosts in this cluster to come up");
                         ex.addProxyObject(cluster.getUuid(), "clusterId");
@@ -780,9 +781,9 @@ private List<HostVO> discoverHostsFull(final Long dcId, final Long podId, Long c
                 }
             }
             clusterId = cluster.getId();
-            if (_clusterDetailsDao.findDetail(clusterId, "cpuOvercommitRatio") == null) {
-                final ClusterDetailsVO cluster_cpu_detail = new ClusterDetailsVO(clusterId, "cpuOvercommitRatio", "1");
-                final ClusterDetailsVO cluster_memory_detail = new ClusterDetailsVO(clusterId, "memoryOvercommitRatio", "1");
+            if (_clusterDetailsDao.findDetail(clusterId, VmDetailConstants.CPU_OVER_COMMIT_RATIO) == null) {
+                final ClusterDetailsVO cluster_cpu_detail = new ClusterDetailsVO(clusterId, VmDetailConstants.CPU_OVER_COMMIT_RATIO, "1");
+                final ClusterDetailsVO cluster_memory_detail = new ClusterDetailsVO(clusterId, VmDetailConstants.MEMORY_OVER_COMMIT_RATIO, "1");
                 _clusterDetailsDao.persist(cluster_cpu_detail);
                 _clusterDetailsDao.persist(cluster_memory_detail);
             }
@@ -964,8 +965,8 @@ public void doInTransactionWithoutResult(final TransactionStatus status) {
                 Host hostRemoved = _hostDao.findById(hostId);
                 _hostDao.remove(hostId);
                 if (clusterId != null) {
-                    final List<HostVO> hosts = listAllHostsInCluster(clusterId);
-                    if (hosts.size() == 0) {
+                    final List<Long> hostIds = _hostDao.listIdsByClusterId(clusterId);
+                    if (CollectionUtils.isEmpty(hostIds)) {
                         final ClusterVO cluster = _clusterDao.findById(clusterId);
                         cluster.setGuid(null);
                         _clusterDao.update(clusterId, cluster);
@@ -1089,11 +1090,9 @@ public void doInTransactionWithoutResult(final TransactionStatus status) {
 
                     final Hypervisor.HypervisorType hypervisorType = cluster.getHypervisorType();
 
-                    final List<HostVO> hosts = listAllHostsInCluster(cmd.getId());
-                    if (hosts.size() > 0) {
-                        if (logger.isDebugEnabled()) {
-                            logger.debug("Cluster: " + cmd.getId() + " still has hosts, can't remove");
-                        }
+                    final List<Long> hostIds = _hostDao.listIdsByClusterId(cmd.getId());
+                    if (!hostIds.isEmpty()) {
+                        logger.debug("Cluster: {} still has hosts, can't remove", cmd.getId());
                         throw new CloudRuntimeException("Cluster: " + cmd.getId() + " cannot be removed. Cluster still has hosts");
                     }
 
@@ -2386,8 +2385,6 @@ protected HostVO createHostVO(final StartupCommand[] cmds, final ServerResource
 
         if (startup instanceof StartupRoutingCommand) {
             final StartupRoutingCommand ssCmd = (StartupRoutingCommand)startup;
-            _hostTagsDao.updateImplicitTags(host.getId(), ssCmd.getHostTags());
-
             updateSupportsClonedVolumes(host, ssCmd.getSupportsClonedVolumes());
         }
 
@@ -2433,10 +2430,10 @@ private void updateSupportsClonedVolumes(HostVO host, boolean supportsClonedVolu
 
         boolean clusterSupportsResigning = true;
 
-        List<HostVO> hostVOs = _hostDao.findByClusterId(host.getClusterId());
+        List<Long> hostIds = _hostDao.listIdsByClusterId(host.getClusterId());
 
-        for (HostVO hostVO : hostVOs) {
-            DetailVO hostDetailVO = _hostDetailsDao.findDetail(hostVO.getId(), name);
+        for (Long hostId : hostIds) {
+            DetailVO hostDetailVO = _hostDetailsDao.findDetail(hostId, name);
 
             if (hostDetailVO == null || Boolean.parseBoolean(hostDetailVO.getValue()) == false) {
                 clusterSupportsResigning = false;
@@ -3050,10 +3047,10 @@ private boolean doUpdateHostPassword(final long hostId) {
     public boolean updateClusterPassword(final UpdateHostPasswordCmd command) {
         final boolean shouldUpdateHostPasswd = command.getUpdatePasswdOnHost();
         // get agents for the cluster
-        final List<HostVO> hosts = listAllHostsInCluster(command.getClusterId());
-        for (final HostVO host : hosts) {
+        final List<Long> hostIds = _hostDao.listIdsByClusterId(command.getClusterId());
+        for (final Long hostId : hostIds) {
             try {
-                final Boolean result = propagateResourceEvent(host.getId(), ResourceState.Event.UpdatePassword);
+                final Boolean result = propagateResourceEvent(hostId, ResourceState.Event.UpdatePassword);
                 if (result != null) {
                     return result;
                 }
@@ -3062,8 +3059,9 @@ public boolean updateClusterPassword(final UpdateHostPasswordCmd command) {
             }
 
             if (shouldUpdateHostPasswd) {
-                final boolean isUpdated = doUpdateHostPassword(host.getId());
+                final boolean isUpdated = doUpdateHostPassword(hostId);
                 if (!isUpdated) {
+                    HostVO host = _hostDao.findById(hostId);
                     throw new CloudRuntimeException(
                             String.format("CloudStack failed to update the password of %s. Please make sure you are still able to connect to your hosts.", host));
                 }
@@ -3278,26 +3276,13 @@ public List<HostVO> listAllHostsInAllZonesByType(final Type type) {
     }
 
     @Override
-    public List<HypervisorType> listAvailHypervisorInZone(final Long hostId, final Long zoneId) {
-        final SearchCriteria<String> sc = _hypervisorsInDC.create();
-        if (zoneId != null) {
-            sc.setParameters("dataCenter", zoneId);
-        }
-        if (hostId != null) {
-            // exclude the given host, since we want to check what hypervisor is already handled
-            // in adding this new host
-            sc.setParameters("id", hostId);
+    public List<HypervisorType> listAvailHypervisorInZone(final Long zoneId) {
+        List<VMTemplateVO> systemVMTemplates = _templateDao.listAllReadySystemVMTemplates(zoneId);
+        final Set<HypervisorType> hypervisors = new HashSet<>();
+        for (final VMTemplateVO systemVMTemplate : systemVMTemplates) {
+            hypervisors.add(systemVMTemplate.getHypervisorType());
         }
-        sc.setParameters("type", Host.Type.Routing);
-
-        // The search is not able to return list of enums, so getting
-        // list of hypervisors as strings and then converting them to enum
-        final List<String> hvs = _hostDao.customSearch(sc, null);
-        final List<HypervisorType> hypervisors = new ArrayList<HypervisorType>();
-        for (final String hv : hvs) {
-            hypervisors.add(HypervisorType.getType(hv));
-        }
-        return hypervisors;
+        return new ArrayList<>(hypervisors);
     }
 
     @Override
@@ -3315,16 +3300,15 @@ public HostVO findHostByName(final String name) {
     }
 
     @Override
-    public HostStats getHostStatistics(final long hostId) {
-        final Answer answer = _agentMgr.easySend(hostId, new GetHostStatsCommand(_hostDao.findById(hostId).getGuid(), _hostDao.findById(hostId).getName(), hostId));
+    public HostStats getHostStatistics(final Host host) {
+        final Answer answer = _agentMgr.easySend(host.getId(), new GetHostStatsCommand(host.getGuid(), host.getName(), host.getId()));
 
         if (answer != null && answer instanceof UnsupportedAnswer) {
             return null;
         }
 
         if (answer == null || !answer.getResult()) {
-            final String msg = "Unable to obtain host " + hostId + " statistics. ";
-            logger.warn(msg);
+            logger.warn("Unable to obtain host {} statistics.", host.getId());
             return null;
         } else {
 
diff --git a/server/src/main/java/com/cloud/resource/RollingMaintenanceManagerImpl.java b/server/src/main/java/com/cloud/resource/RollingMaintenanceManagerImpl.java
index c7bdf9c6f6c9..37dceed901b6 100644
--- a/server/src/main/java/com/cloud/resource/RollingMaintenanceManagerImpl.java
+++ b/server/src/main/java/com/cloud/resource/RollingMaintenanceManagerImpl.java
@@ -636,7 +636,7 @@ private Pair<Boolean, String> performCapacityChecksBeforeHostInMaintenance(Host
                     continue;
                 }
                 boolean maxGuestLimit = capacityManager.checkIfHostReachMaxGuestLimit(host);
-                boolean hostHasCPUCapacity = capacityManager.checkIfHostHasCpuCapability(hostInCluster.getId(), serviceOffering.getCpu(), serviceOffering.getSpeed());
+                boolean hostHasCPUCapacity = capacityManager.checkIfHostHasCpuCapability(hostInCluster, serviceOffering.getCpu(), serviceOffering.getSpeed());
                 int cpuRequested = serviceOffering.getCpu() * serviceOffering.getSpeed();
                 long ramRequested = serviceOffering.getRamSize() * 1024L * 1024L;
                 ClusterDetailsVO clusterDetailsCpuOvercommit = clusterDetailsDao.findDetail(cluster.getId(), "cpuOvercommitRatio");
diff --git a/server/src/main/java/com/cloud/resourcelimit/ResourceLimitManagerImpl.java b/server/src/main/java/com/cloud/resourcelimit/ResourceLimitManagerImpl.java
index b59ddc029ee1..cc649ed21ecb 100644
--- a/server/src/main/java/com/cloud/resourcelimit/ResourceLimitManagerImpl.java
+++ b/server/src/main/java/com/cloud/resourcelimit/ResourceLimitManagerImpl.java
@@ -93,7 +93,6 @@
 import com.cloud.projects.ProjectAccount.Role;
 import com.cloud.projects.dao.ProjectAccountDao;
 import com.cloud.projects.dao.ProjectDao;
-import com.cloud.service.ServiceOfferingVO;
 import com.cloud.service.dao.ServiceOfferingDao;
 import com.cloud.storage.DataStoreRole;
 import com.cloud.storage.DiskOfferingVO;
@@ -105,7 +104,6 @@
 import com.cloud.storage.dao.SnapshotDao;
 import com.cloud.storage.dao.VMTemplateDao;
 import com.cloud.storage.dao.VolumeDao;
-import com.cloud.storage.dao.VolumeDaoImpl.SumCount;
 import com.cloud.template.VirtualMachineTemplate;
 import com.cloud.user.Account;
 import com.cloud.user.AccountManager;
@@ -118,6 +116,7 @@
 import com.cloud.utils.db.DB;
 import com.cloud.utils.db.EntityManager;
 import com.cloud.utils.db.Filter;
+import com.cloud.utils.db.GenericDaoBase.SumCount;
 import com.cloud.utils.db.GenericSearchBuilder;
 import com.cloud.utils.db.GlobalLock;
 import com.cloud.utils.db.JoinBuilder;
@@ -1291,16 +1290,14 @@ protected List<UserVmJoinVO> getVmsWithAccountAndTag(long accountId, String tag)
         if (StringUtils.isEmpty(tag)) {
             return _userVmJoinDao.listByAccountServiceOfferingTemplateAndNotInState(accountId, states, null, null);
         }
-        List<ServiceOfferingVO> offerings = serviceOfferingDao.listByHostTag(tag);
-        List<VMTemplateVO> templates = _vmTemplateDao.listByTemplateTag(tag);
+        List<Long> offerings = serviceOfferingDao.listIdsByHostTag(tag);
+        List<Long> templates = _vmTemplateDao.listIdsByTemplateTag(tag);
         if (CollectionUtils.isEmpty(offerings) && CollectionUtils.isEmpty(templates)) {
             return new ArrayList<>();
         }
 
         return  _userVmJoinDao.listByAccountServiceOfferingTemplateAndNotInState(accountId, states,
-                offerings.stream().map(ServiceOfferingVO::getId).collect(Collectors.toList()),
-                templates.stream().map(VMTemplateVO::getId).collect(Collectors.toList())
-        );
+                offerings, templates);
     }
 
     protected List<UserVmJoinVO> getVmsWithAccount(long accountId) {
diff --git a/server/src/main/java/com/cloud/server/ManagementServerImpl.java b/server/src/main/java/com/cloud/server/ManagementServerImpl.java
index 87b3dd3cbd92..80c2f618ef3b 100644
--- a/server/src/main/java/com/cloud/server/ManagementServerImpl.java
+++ b/server/src/main/java/com/cloud/server/ManagementServerImpl.java
@@ -44,7 +44,6 @@
 import javax.inject.Inject;
 import javax.naming.ConfigurationException;
 
-import com.cloud.utils.security.CertificateHelper;
 import org.apache.cloudstack.acl.ControlledEntity;
 import org.apache.cloudstack.acl.SecurityChecker;
 import org.apache.cloudstack.affinity.AffinityGroupProcessor;
@@ -71,7 +70,6 @@
 import org.apache.cloudstack.api.command.admin.bgp.CreateASNRangeCmd;
 import org.apache.cloudstack.api.command.admin.bgp.DeleteASNRangeCmd;
 import org.apache.cloudstack.api.command.admin.bgp.ListASNRangesCmd;
-import org.apache.cloudstack.api.command.user.bgp.ListASNumbersCmd;
 import org.apache.cloudstack.api.command.admin.bgp.ReleaseASNumberCmd;
 import org.apache.cloudstack.api.command.admin.cluster.AddClusterCmd;
 import org.apache.cloudstack.api.command.admin.cluster.DeleteClusterCmd;
@@ -297,6 +295,7 @@
 import org.apache.cloudstack.api.command.admin.vm.DestroyVMCmdByAdmin;
 import org.apache.cloudstack.api.command.admin.vm.ExpungeVMCmd;
 import org.apache.cloudstack.api.command.admin.vm.GetVMUserDataCmd;
+import org.apache.cloudstack.api.command.admin.vm.ListAffectedVmsForStorageScopeChangeCmd;
 import org.apache.cloudstack.api.command.admin.vm.ListVMsCmdByAdmin;
 import org.apache.cloudstack.api.command.admin.vm.MigrateVMCmd;
 import org.apache.cloudstack.api.command.admin.vm.MigrateVirtualMachineWithVolumeCmd;
@@ -376,6 +375,7 @@
 import org.apache.cloudstack.api.command.user.autoscale.UpdateAutoScaleVmGroupCmd;
 import org.apache.cloudstack.api.command.user.autoscale.UpdateAutoScaleVmProfileCmd;
 import org.apache.cloudstack.api.command.user.autoscale.UpdateConditionCmd;
+import org.apache.cloudstack.api.command.user.bgp.ListASNumbersCmd;
 import org.apache.cloudstack.api.command.user.bucket.CreateBucketCmd;
 import org.apache.cloudstack.api.command.user.bucket.DeleteBucketCmd;
 import org.apache.cloudstack.api.command.user.bucket.ListBucketsCmd;
@@ -532,7 +532,6 @@
 import org.apache.cloudstack.api.command.user.vm.AddNicToVMCmd;
 import org.apache.cloudstack.api.command.user.vm.DeployVMCmd;
 import org.apache.cloudstack.api.command.user.vm.DestroyVMCmd;
-import org.apache.cloudstack.api.command.admin.vm.ListAffectedVmsForStorageScopeChangeCmd;
 import org.apache.cloudstack.api.command.user.vm.GetVMPasswordCmd;
 import org.apache.cloudstack.api.command.user.vm.ListNicsCmd;
 import org.apache.cloudstack.api.command.user.vm.ListVMsCmd;
@@ -825,6 +824,7 @@
 import com.cloud.utils.fsm.StateMachine2;
 import com.cloud.utils.net.MacAddress;
 import com.cloud.utils.net.NetUtils;
+import com.cloud.utils.security.CertificateHelper;
 import com.cloud.utils.ssh.SSHKeysHelper;
 import com.cloud.vm.ConsoleProxyVO;
 import com.cloud.vm.DiskProfile;
@@ -5048,7 +5048,7 @@ public String getVMPassword(GetVMPasswordCmd cmd) {
 
     private boolean updateHostsInCluster(final UpdateHostPasswordCmd command) {
         // get all the hosts in this cluster
-        final List<HostVO> hosts = _resourceMgr.listAllHostsInCluster(command.getClusterId());
+        final List<Long> hostIds = _hostDao.listIdsByClusterId(command.getClusterId());
 
         String userNameWithoutSpaces = StringUtils.deleteWhitespace(command.getUsername());
         if (StringUtils.isBlank(userNameWithoutSpaces)) {
@@ -5058,19 +5058,17 @@ private boolean updateHostsInCluster(final UpdateHostPasswordCmd command) {
         Transaction.execute(new TransactionCallbackNoReturn() {
             @Override
             public void doInTransactionWithoutResult(final TransactionStatus status) {
-                for (final HostVO h : hosts) {
-                    if (logger.isDebugEnabled()) {
-                        logger.debug("Changing password for host name = " + h.getName());
-                    }
+                for (final Long hostId : hostIds) {
+                    logger.debug("Changing password for host ID: {}", hostId);
                     // update password for this host
-                    final DetailVO nv = _detailsDao.findDetail(h.getId(), ApiConstants.USERNAME);
+                    final DetailVO nv = _detailsDao.findDetail(hostId, ApiConstants.USERNAME);
                     if (nv == null) {
-                        final DetailVO nvu = new DetailVO(h.getId(), ApiConstants.USERNAME, userNameWithoutSpaces);
+                        final DetailVO nvu = new DetailVO(hostId, ApiConstants.USERNAME, userNameWithoutSpaces);
                         _detailsDao.persist(nvu);
-                        final DetailVO nvp = new DetailVO(h.getId(), ApiConstants.PASSWORD, DBEncryptionUtil.encrypt(command.getPassword()));
+                        final DetailVO nvp = new DetailVO(hostId, ApiConstants.PASSWORD, DBEncryptionUtil.encrypt(command.getPassword()));
                         _detailsDao.persist(nvp);
                     } else if (nv.getValue().equals(userNameWithoutSpaces)) {
-                        final DetailVO nvp = _detailsDao.findDetail(h.getId(), ApiConstants.PASSWORD);
+                        final DetailVO nvp = _detailsDao.findDetail(hostId, ApiConstants.PASSWORD);
                         nvp.setValue(DBEncryptionUtil.encrypt(command.getPassword()));
                         _detailsDao.persist(nvp);
                     } else {
diff --git a/server/src/main/java/com/cloud/server/StatsCollector.java b/server/src/main/java/com/cloud/server/StatsCollector.java
index 70959b56cfde..4c88fa24326e 100644
--- a/server/src/main/java/com/cloud/server/StatsCollector.java
+++ b/server/src/main/java/com/cloud/server/StatsCollector.java
@@ -42,6 +42,7 @@
 import java.util.concurrent.Executors;
 import java.util.concurrent.ScheduledExecutorService;
 import java.util.concurrent.TimeUnit;
+import java.util.stream.Collectors;
 
 import javax.inject.Inject;
 
@@ -131,6 +132,7 @@
 import com.cloud.user.dao.VmDiskStatisticsDao;
 import com.cloud.utils.LogUtils;
 import com.cloud.utils.NumbersUtil;
+import com.cloud.utils.Pair;
 import com.cloud.utils.component.ComponentMethodInterceptable;
 import com.cloud.utils.component.ManagerBase;
 import com.cloud.utils.concurrency.NamedThreadFactory;
@@ -147,7 +149,6 @@
 import com.cloud.utils.script.Script;
 import com.cloud.vm.NicVO;
 import com.cloud.vm.UserVmManager;
-import com.cloud.vm.UserVmVO;
 import com.cloud.vm.VMInstanceVO;
 import com.cloud.vm.VirtualMachine;
 import com.cloud.vm.VirtualMachineManager;
@@ -623,17 +624,21 @@ protected int retrieveExternalStatsPortFromUri(URI uri) throws URISyntaxExceptio
                 externalStatsPrefix, externalStatsHost, externalStatsPort));
     }
 
-    protected Map<Long, VMInstanceVO> getVmMapForStatsForHost(Host host) {
+    protected Pair<Map<Long, VMInstanceVO>, Map<String, Long>> getVmMapForStatsForHost(Host host) {
         List<VMInstanceVO> vms = _vmInstance.listByHostAndState(host.getId(), VirtualMachine.State.Running);
         boolean collectUserVMStatsOnly = Boolean.TRUE.equals(vmStatsCollectUserVMOnly.value());
-        Map<Long, VMInstanceVO> vmMap = new HashMap<>();
-        for (VMInstanceVO vm : vms) {
-            if (collectUserVMStatsOnly && !VirtualMachine.Type.User.equals(vm.getType())) {
-                continue;
+        if (collectUserVMStatsOnly) {
+            vms = vms.stream().filter(vm -> VirtualMachine.Type.User.equals(vm.getType())).collect(Collectors.toList());
+        }
+        Map<Long, VMInstanceVO> idInstanceMap = new HashMap<>();
+        Map<String, Long> instanceNameIdMap = new HashMap<>();
+        vms.forEach(vm -> {
+            if (!collectUserVMStatsOnly || VirtualMachine.Type.User.equals(vm.getType())) {
+                idInstanceMap.put(vm.getId(), vm);
+                instanceNameIdMap.put(vm.getInstanceName(), vm.getId());
             }
-            vmMap.put(vm.getId(), vm);
-        }
-        return vmMap;
+        });
+        return new Pair<>(idInstanceMap, instanceNameIdMap);
     }
 
     class HostCollector extends AbstractStatsCollector {
@@ -647,7 +652,7 @@ protected void runInContext() {
 
                 Map<Object, Object> metrics = new HashMap<>();
                 for (HostVO host : hosts) {
-                    HostStatsEntry hostStatsEntry = (HostStatsEntry) _resourceMgr.getHostStatistics(host.getId());
+                    HostStatsEntry hostStatsEntry = (HostStatsEntry) _resourceMgr.getHostStatistics(host);
                     if (hostStatsEntry != null) {
                         hostStatsEntry.setHostVo(host);
                         metrics.put(hostStatsEntry.getHostId(), hostStatsEntry);
@@ -1195,37 +1200,39 @@ protected void runInContext() {
                 Map<Object, Object> metrics = new HashMap<>();
                 for (HostVO host : hosts) {
                     Date timestamp = new Date();
-                    Map<Long, VMInstanceVO> vmMap = getVmMapForStatsForHost(host);
+                    Pair<Map<Long, VMInstanceVO>, Map<String, Long>> vmsAndMap = getVmMapForStatsForHost(host);
+                    Map<Long, VMInstanceVO> vmMap = vmsAndMap.first();
                     try {
-                        Map<Long, ? extends VmStats> vmStatsById = virtualMachineManager.getVirtualMachineStatistics(host.getId(), host.getName(), vmMap);
-
-                        if (vmStatsById != null) {
-                            Set<Long> vmIdSet = vmStatsById.keySet();
-                            for (Long vmId : vmIdSet) {
-                                VmStatsEntry statsForCurrentIteration = (VmStatsEntry)vmStatsById.get(vmId);
-                                statsForCurrentIteration.setVmId(vmId);
-                                VMInstanceVO vm = vmMap.get(vmId);
-                                statsForCurrentIteration.setVmUuid(vm.getUuid());
-
-                                persistVirtualMachineStats(statsForCurrentIteration, timestamp);
-
-                                if (externalStatsType == ExternalStatsProtocol.GRAPHITE) {
-                                    prepareVmMetricsForGraphite(metrics, statsForCurrentIteration);
-                                } else {
-                                    metrics.put(statsForCurrentIteration.getVmId(), statsForCurrentIteration);
-                                }
+                        Map<Long, ? extends VmStats> vmStatsById = virtualMachineManager.getVirtualMachineStatistics(
+                                host, vmsAndMap.second());
+                        if (MapUtils.isEmpty(vmStatsById)) {
+                            continue;
+                        }
+                        Set<Long> vmIdSet = vmStatsById.keySet();
+                        for (Long vmId : vmIdSet) {
+                            VmStatsEntry statsForCurrentIteration = (VmStatsEntry)vmStatsById.get(vmId);
+                            statsForCurrentIteration.setVmId(vmId);
+                            VMInstanceVO vm = vmMap.get(vmId);
+                            statsForCurrentIteration.setVmUuid(vm.getUuid());
+
+                            persistVirtualMachineStats(statsForCurrentIteration, timestamp);
+
+                            if (externalStatsType == ExternalStatsProtocol.GRAPHITE) {
+                                prepareVmMetricsForGraphite(metrics, statsForCurrentIteration);
+                            } else {
+                                metrics.put(statsForCurrentIteration.getVmId(), statsForCurrentIteration);
                             }
+                        }
 
-                            if (!metrics.isEmpty()) {
-                                if (externalStatsType == ExternalStatsProtocol.GRAPHITE) {
-                                    sendVmMetricsToGraphiteHost(metrics, host);
-                                } else if (externalStatsType == ExternalStatsProtocol.INFLUXDB) {
-                                    sendMetricsToInfluxdb(metrics);
-                                }
+                        if (!metrics.isEmpty()) {
+                            if (externalStatsType == ExternalStatsProtocol.GRAPHITE) {
+                                sendVmMetricsToGraphiteHost(metrics, host);
+                            } else if (externalStatsType == ExternalStatsProtocol.INFLUXDB) {
+                                sendMetricsToInfluxdb(metrics);
                             }
-
-                            metrics.clear();
                         }
+
+                        metrics.clear();
                     } catch (Exception e) {
                         logger.debug("Failed to get VM stats for host with ID: " + host.getId());
                         continue;
@@ -1413,8 +1420,10 @@ protected void runInContext() {
                     Transaction.execute(new TransactionCallbackNoReturn() {
                         @Override
                         public void doInTransactionWithoutResult(TransactionStatus status) {
-                            Map<Long, VMInstanceVO> vmMap = getVmMapForStatsForHost(host);
-                            HashMap<Long, List<? extends VmDiskStats>> vmDiskStatsById = virtualMachineManager.getVmDiskStatistics(host.getId(), host.getName(), vmMap);
+                            Pair<Map<Long, VMInstanceVO>, Map<String, Long>> vmsAndMap = getVmMapForStatsForHost(host);
+                            Map<Long, VMInstanceVO> vmMap = vmsAndMap.first();
+                            HashMap<Long, List<? extends VmDiskStats>> vmDiskStatsById =
+                                    virtualMachineManager.getVmDiskStatistics(host, vmsAndMap.second());
                             if (vmDiskStatsById == null)
                                 return;
 
@@ -1521,8 +1530,10 @@ protected void runInContext() {
                     Transaction.execute(new TransactionCallbackNoReturn() {
                         @Override
                         public void doInTransactionWithoutResult(TransactionStatus status) {
-                            Map<Long, VMInstanceVO> vmMap = getVmMapForStatsForHost(host);
-                            HashMap<Long, List<? extends VmNetworkStats>> vmNetworkStatsById = virtualMachineManager.getVmNetworkStatistics(host.getId(), host.getName(), vmMap);
+                            Pair<Map<Long, VMInstanceVO>, Map<String, Long>> vmsAndMap = getVmMapForStatsForHost(host);
+                            Map<Long, VMInstanceVO> vmMap = vmsAndMap.first();
+                            HashMap<Long, List<? extends VmNetworkStats>> vmNetworkStatsById =
+                                    virtualMachineManager.getVmNetworkStatistics(host, vmsAndMap.second());
                             if (vmNetworkStatsById == null)
                                 return;
 
@@ -1531,9 +1542,9 @@ public void doInTransactionWithoutResult(TransactionStatus status) {
                                 List<? extends VmNetworkStats> vmNetworkStats = vmNetworkStatsById.get(vmId);
                                 if (CollectionUtils.isEmpty(vmNetworkStats))
                                     continue;
-                                UserVmVO userVm = _userVmDao.findById(vmId);
-                                if (userVm == null) {
-                                    logger.debug("Cannot find uservm with id: " + vmId + " , continue");
+                                VMInstanceVO userVm = vmMap.get(vmId);
+                                if (!VirtualMachine.Type.User.equals(userVm.getType())) {
+                                    logger.debug("Cannot find uservm with id: {} , continue", vmId);
                                     continue;
                                 }
                                 logger.debug("Now we are updating the user_statistics table for VM: " + userVm.getInstanceName()
diff --git a/server/src/main/java/com/cloud/storage/StorageManagerImpl.java b/server/src/main/java/com/cloud/storage/StorageManagerImpl.java
index 2ed6be39b543..ce1da8ce4716 100644
--- a/server/src/main/java/com/cloud/storage/StorageManagerImpl.java
+++ b/server/src/main/java/com/cloud/storage/StorageManagerImpl.java
@@ -42,10 +42,14 @@
 import java.util.Random;
 import java.util.Set;
 import java.util.UUID;
+import java.util.concurrent.CopyOnWriteArrayList;
 import java.util.concurrent.ExecutionException;
+import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
+import java.util.concurrent.Future;
 import java.util.concurrent.ScheduledExecutorService;
 import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.stream.Collectors;
 
 import javax.inject.Inject;
@@ -62,8 +66,8 @@
 import org.apache.cloudstack.api.command.admin.storage.DeletePoolCmd;
 import org.apache.cloudstack.api.command.admin.storage.DeleteSecondaryStagingStoreCmd;
 import org.apache.cloudstack.api.command.admin.storage.SyncStoragePoolCmd;
-import org.apache.cloudstack.api.command.admin.storage.UpdateObjectStoragePoolCmd;
 import org.apache.cloudstack.api.command.admin.storage.UpdateImageStoreCmd;
+import org.apache.cloudstack.api.command.admin.storage.UpdateObjectStoragePoolCmd;
 import org.apache.cloudstack.api.command.admin.storage.UpdateStoragePoolCmd;
 import org.apache.cloudstack.api.command.admin.storage.heuristics.CreateSecondaryStorageSelectorCmd;
 import org.apache.cloudstack.api.command.admin.storage.heuristics.RemoveSecondaryStorageSelectorCmd;
@@ -86,6 +90,7 @@
 import org.apache.cloudstack.engine.subsystem.api.storage.PrimaryDataStoreInfo;
 import org.apache.cloudstack.engine.subsystem.api.storage.PrimaryDataStoreLifeCycle;
 import org.apache.cloudstack.engine.subsystem.api.storage.PrimaryDataStoreProvider;
+import org.apache.cloudstack.engine.subsystem.api.storage.Scope;
 import org.apache.cloudstack.engine.subsystem.api.storage.SnapshotDataFactory;
 import org.apache.cloudstack.engine.subsystem.api.storage.SnapshotInfo;
 import org.apache.cloudstack.engine.subsystem.api.storage.SnapshotService;
@@ -234,8 +239,8 @@
 import com.cloud.utils.DateUtil;
 import com.cloud.utils.NumbersUtil;
 import com.cloud.utils.Pair;
-import com.cloud.utils.UriUtils;
 import com.cloud.utils.StringUtils;
+import com.cloud.utils.UriUtils;
 import com.cloud.utils.component.ComponentContext;
 import com.cloud.utils.component.ManagerBase;
 import com.cloud.utils.concurrency.NamedThreadFactory;
@@ -1540,6 +1545,68 @@ protected String getStoragePoolNonDestroyedVolumesLog(long storagePoolId) {
         return sb.toString();
     }
 
+    protected void cleanupConnectedHostConnectionForFailedStorage(DataStore primaryStore, List<Long> poolHostIds) {
+        for (Long hostId : poolHostIds) {
+            try {
+                disconnectHostFromSharedPool(hostId, primaryStore.getId());
+            } catch (StorageUnavailableException | StorageConflictException e) {
+                logger.error("Error during cleaning up failed storage host connection", e);
+            }
+        }
+    }
+
+    @Override
+    public void connectHostsToPool(DataStore primaryStore, List<Long> hostIds, Scope scope,
+              boolean handleStorageConflictException, boolean errorOnNoUpHost) throws CloudRuntimeException {
+        CopyOnWriteArrayList<Long> poolHostIds = new CopyOnWriteArrayList<>();
+        ExecutorService executorService = Executors.newFixedThreadPool(Math.max(1, Math.min(hostIds.size(),
+                StoragePoolHostConnectWorkers.value())));
+        List<Future<Void>> futures = new ArrayList<>();
+        AtomicBoolean conflictSeen = new AtomicBoolean(false);
+        for (Long hostId : hostIds) {
+            futures.add(executorService.submit(() -> {
+                if (conflictSeen.get()) {
+                    return null;
+                }
+                try {
+                    connectHostToSharedPool(hostId, primaryStore.getId());
+                    poolHostIds.add(hostId);
+                } catch (Exception e) {
+                    if (handleStorageConflictException && e.getCause() instanceof StorageConflictException) {
+                        conflictSeen.set(true);
+                        throw e;
+                    }
+                    HostVO host = _hostDao.findById(hostId);
+                    logger.warn("Unable to establish a connection between {} and {}", host, primaryStore, e);
+                }
+                return null;
+            }));
+        }
+        for (Future<Void> future : futures) {
+            try {
+                future.get();
+            } catch (Exception e) {
+                if (e.getCause() instanceof StorageConflictException) {
+                    executorService.shutdown();
+                    cleanupConnectedHostConnectionForFailedStorage(primaryStore, poolHostIds);
+                    primaryStoreDao.expunge(primaryStore.getId());
+                    throw new CloudRuntimeException("Storage has already been added as local storage", e);
+                } else {
+                    logger.error("Error occurred while connecting host to shared pool", e);
+                }
+            }
+        }
+        executorService.shutdown();
+        if (poolHostIds.isEmpty()) {
+            logger.warn("No host can access storage pool {} in {}: {}.",
+                    primaryStore, scope.getScopeType(), scope.getScopeId());
+            if (errorOnNoUpHost) {
+                primaryStoreDao.expunge(primaryStore.getId());
+                throw new CloudRuntimeException("Failed to access storage pool");
+            }
+        }
+    }
+
     @Override
     public boolean connectHostToSharedPool(long hostId, long poolId) throws StorageUnavailableException, StorageConflictException {
         StoragePool pool = (StoragePool)_dataStoreMgr.getDataStore(poolId, DataStoreRole.Primary);
@@ -4050,7 +4117,8 @@ public ConfigKey<?>[] getConfigKeys() {
                 MountDisabledStoragePool,
                 VmwareCreateCloneFull,
                 VmwareAllowParallelExecution,
-                DataStoreDownloadFollowRedirects
+                DataStoreDownloadFollowRedirects,
+                StoragePoolHostConnectWorkers
         };
     }
 
diff --git a/server/src/main/java/com/cloud/storage/download/DownloadListener.java b/server/src/main/java/com/cloud/storage/download/DownloadListener.java
index bd0c0eff1bce..7d17a69cf7d7 100644
--- a/server/src/main/java/com/cloud/storage/download/DownloadListener.java
+++ b/server/src/main/java/com/cloud/storage/download/DownloadListener.java
@@ -16,6 +16,7 @@
 // under the License.
 package com.cloud.storage.download;
 
+import java.util.Collections;
 import java.util.Date;
 import java.util.HashMap;
 import java.util.List;
@@ -24,10 +25,6 @@
 
 import javax.inject.Inject;
 
-import org.apache.logging.log4j.Level;
-import org.apache.logging.log4j.Logger;
-import org.apache.logging.log4j.LogManager;
-
 import org.apache.cloudstack.engine.subsystem.api.storage.DataObject;
 import org.apache.cloudstack.engine.subsystem.api.storage.DataStore;
 import org.apache.cloudstack.engine.subsystem.api.storage.DataStoreManager;
@@ -41,6 +38,10 @@
 import org.apache.cloudstack.storage.command.DownloadCommand.ResourceType;
 import org.apache.cloudstack.storage.command.DownloadProgressCommand;
 import org.apache.cloudstack.storage.command.DownloadProgressCommand.RequestType;
+import org.apache.cloudstack.utils.cache.LazyCache;
+import org.apache.logging.log4j.Level;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
 
 import com.cloud.agent.Listener;
 import com.cloud.agent.api.AgentControlAnswer;
@@ -54,7 +55,7 @@
 import com.cloud.agent.api.to.DataObjectType;
 import com.cloud.exception.ConnectionException;
 import com.cloud.host.Host;
-import com.cloud.hypervisor.Hypervisor.HypervisorType;
+import com.cloud.hypervisor.Hypervisor;
 import com.cloud.resource.ResourceManager;
 import com.cloud.storage.VMTemplateStorageResourceAssoc.Status;
 import com.cloud.storage.download.DownloadState.DownloadEvent;
@@ -136,6 +137,20 @@ protected void runInContext() {
     @Inject
     private VolumeService _volumeSrv;
 
+    private LazyCache<Long, List<Hypervisor.HypervisorType>> zoneHypervisorsCache;
+
+    private List<Hypervisor.HypervisorType> listAvailHypervisorInZone(long zoneId) {
+        if (_resourceMgr == null) {
+            return Collections.emptyList();
+        }
+        return _resourceMgr.listAvailHypervisorInZone(zoneId);
+    }
+
+    protected void initZoneHypervisorsCache() {
+        zoneHypervisorsCache =
+                new LazyCache<>(32, 30, this::listAvailHypervisorInZone);
+    }
+
     // TODO: this constructor should be the one used for template only, remove other template constructor later
     public DownloadListener(EndPoint ssAgent, DataStore store, DataObject object, Timer timer, DownloadMonitorImpl downloadMonitor, DownloadCommand cmd,
             AsyncCompletionCallback<DownloadAnswer> callback) {
@@ -151,6 +166,12 @@ public DownloadListener(EndPoint ssAgent, DataStore store, DataObject object, Ti
         _callback = callback;
         DownloadAnswer answer = new DownloadAnswer("", Status.NOT_DOWNLOADED);
         callback(answer);
+        initZoneHypervisorsCache();
+    }
+
+    public DownloadListener(DownloadMonitorImpl monitor) {
+        _downloadMonitor = monitor;
+        initZoneHypervisorsCache();
     }
 
     public AsyncCompletionCallback<DownloadAnswer> getCallback() {
@@ -210,10 +231,6 @@ public void log(String message, Level level) {
         logger.log(level, message + ", " + object.getType() + ": " + object.getId() + " at host " + _ssAgent.getId());
     }
 
-    public DownloadListener(DownloadMonitorImpl monitor) {
-        _downloadMonitor = monitor;
-    }
-
     @Override
     public boolean isRecurring() {
         return false;
@@ -278,14 +295,15 @@ public void processHostAdded(long hostId) {
     @Override
     public void processConnect(Host agent, StartupCommand cmd, boolean forRebalance) throws ConnectionException {
         if (cmd instanceof StartupRoutingCommand) {
-            List<HypervisorType> hypers = _resourceMgr.listAvailHypervisorInZone(agent.getId(), agent.getDataCenterId());
-            HypervisorType hostHyper = agent.getHypervisorType();
-            if (hypers.contains(hostHyper)) {
+            List<Hypervisor.HypervisorType> hypervisors = zoneHypervisorsCache.get(agent.getDataCenterId());
+            Hypervisor.HypervisorType hostHyper = agent.getHypervisorType();
+            if (hypervisors.contains(hostHyper)) {
                 return;
             }
             _imageSrv.handleSysTemplateDownload(hostHyper, agent.getDataCenterId());
             // update template_zone_ref for cross-zone templates
             _imageSrv.associateCrosszoneTemplatesToZone(agent.getDataCenterId());
+
         }
         /* This can be removed
         else if ( cmd instanceof StartupStorageCommand) {
diff --git a/server/src/main/java/com/cloud/vm/UserVmManagerImpl.java b/server/src/main/java/com/cloud/vm/UserVmManagerImpl.java
index 219feeef5a91..a0e0df1844f7 100644
--- a/server/src/main/java/com/cloud/vm/UserVmManagerImpl.java
+++ b/server/src/main/java/com/cloud/vm/UserVmManagerImpl.java
@@ -2112,7 +2112,7 @@ private boolean upgradeRunningVirtualMachine(Long vmId, Long newServiceOfferingI
 
                     // #1 Check existing host has capacity & and the correct tags
                     if (!excludes.shouldAvoid(ApiDBUtils.findHostById(vmInstance.getHostId()))) {
-                        existingHostHasCapacity = _capacityMgr.checkIfHostHasCpuCapability(vmInstance.getHostId(), newCpu, newSpeed)
+                        existingHostHasCapacity = _capacityMgr.checkIfHostHasCpuCapability(host, newCpu, newSpeed)
                                 && _capacityMgr.checkIfHostHasCapacity(vmInstance.getHostId(), cpuDiff, ByteScaleUtils.mebibytesToBytes(memoryDiff), false,
                                         _capacityMgr.getClusterOverProvisioningFactor(host.getClusterId(), Capacity.CAPACITY_TYPE_CPU),
                                         _capacityMgr.getClusterOverProvisioningFactor(host.getClusterId(), Capacity.CAPACITY_TYPE_MEMORY), false)
diff --git a/server/src/main/java/org/apache/cloudstack/acl/RoleManagerImpl.java b/server/src/main/java/org/apache/cloudstack/acl/RoleManagerImpl.java
index 60e7093c48b3..396be78d76b2 100644
--- a/server/src/main/java/org/apache/cloudstack/acl/RoleManagerImpl.java
+++ b/server/src/main/java/org/apache/cloudstack/acl/RoleManagerImpl.java
@@ -92,6 +92,7 @@ public void checkCallerAccess() {
 
     @Override
     public boolean isEnabled() {
+        // FIXME: hotspot, could be cached?
         return RoleService.EnableDynamicApiChecker.value();
     }
 
@@ -594,7 +595,7 @@ public String getConfigComponentName() {
 
     @Override
     public ConfigKey<?>[] getConfigKeys() {
-        return new ConfigKey<?>[] {RoleService.EnableDynamicApiChecker};
+        return new ConfigKey<?>[] {RoleService.EnableDynamicApiChecker, RoleService.DynamicApiCheckerCachePeriod};
     }
 
     @Override
diff --git a/server/src/main/java/org/apache/cloudstack/agent/lb/IndirectAgentLBServiceImpl.java b/server/src/main/java/org/apache/cloudstack/agent/lb/IndirectAgentLBServiceImpl.java
index 8b05a76d0a96..84c3081bfc1b 100644
--- a/server/src/main/java/org/apache/cloudstack/agent/lb/IndirectAgentLBServiceImpl.java
+++ b/server/src/main/java/org/apache/cloudstack/agent/lb/IndirectAgentLBServiceImpl.java
@@ -18,9 +18,7 @@
 
 import java.util.ArrayList;
 import java.util.Arrays;
-import java.util.Collections;
 import java.util.Comparator;
-import java.util.EnumSet;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
@@ -34,17 +32,19 @@
 import org.apache.cloudstack.config.ApiServiceConfiguration;
 import org.apache.cloudstack.framework.config.ConfigKey;
 import org.apache.cloudstack.framework.config.Configurable;
+import org.apache.commons.lang3.StringUtils;
 
 import com.cloud.agent.AgentManager;
 import com.cloud.agent.api.Answer;
+import com.cloud.dc.DataCenterVO;
+import com.cloud.dc.dao.ClusterDao;
+import com.cloud.dc.dao.DataCenterDao;
 import com.cloud.host.Host;
-import com.cloud.host.HostVO;
 import com.cloud.host.dao.HostDao;
 import com.cloud.hypervisor.Hypervisor;
 import com.cloud.resource.ResourceState;
 import com.cloud.utils.component.ComponentLifecycleBase;
 import com.cloud.utils.exception.CloudRuntimeException;
-import org.apache.commons.lang3.StringUtils;
 
 public class IndirectAgentLBServiceImpl extends ComponentLifecycleBase implements IndirectAgentLB, Configurable {
 
@@ -60,11 +60,23 @@ public class IndirectAgentLBServiceImpl extends ComponentLifecycleBase implement
 
     private static Map<String, org.apache.cloudstack.agent.lb.IndirectAgentLBAlgorithm> algorithmMap = new HashMap<>();
 
+    @Inject
+    private DataCenterDao dataCenterDao;
+    @Inject
+    private ClusterDao clusterDao;
     @Inject
     private HostDao hostDao;
     @Inject
     private AgentManager agentManager;
 
+    private static final List<ResourceState> agentValidResourceStates = List.of(
+            ResourceState.Enabled, ResourceState.Maintenance, ResourceState.Disabled,
+            ResourceState.ErrorInMaintenance, ResourceState.PrepareForMaintenance);
+    private static final List<Host.Type> agentValidHostTypes = List.of(Host.Type.Routing, Host.Type.ConsoleProxy,
+            Host.Type.SecondaryStorage, Host.Type.SecondaryStorageVM);
+    private static final List<Hypervisor.HypervisorType> agentValidHypervisorTypes = List.of(
+            Hypervisor.HypervisorType.KVM, Hypervisor.HypervisorType.LXC);
+
     //////////////////////////////////////////////////////
     /////////////// Agent MSLB Methods ///////////////////
     //////////////////////////////////////////////////////
@@ -76,22 +88,22 @@ public List<String> getManagementServerList(final Long hostId, final Long dcId,
             throw new CloudRuntimeException(String.format("No management server addresses are defined in '%s' setting",
                     ApiServiceConfiguration.ManagementServerAddresses.key()));
         }
+        final List<String> msList = Arrays.asList(msServerAddresses.replace(" ", "").split(","));
+        if (msList.size() == 1) {
+            return msList;
+        }
 
+        final org.apache.cloudstack.agent.lb.IndirectAgentLBAlgorithm algorithm = getAgentMSLBAlgorithm();
         List<Long> hostIdList = orderedHostIdList;
         if (hostIdList == null) {
-            hostIdList = getOrderedHostIdList(dcId);
+            hostIdList = algorithm.isHostListNeeded() ? getOrderedHostIdList(dcId) : new ArrayList<>();
         }
 
         // just in case we have a host in creating state make sure it is in the list:
         if (null != hostId && ! hostIdList.contains(hostId)) {
-            if (logger.isTraceEnabled()) {
-                logger.trace("adding requested host to host list as it does not seem to be there; " + hostId);
-            }
+            logger.trace("adding requested host to host list as it does not seem to be there; {}", hostId);
             hostIdList.add(hostId);
         }
-
-        final org.apache.cloudstack.agent.lb.IndirectAgentLBAlgorithm algorithm = getAgentMSLBAlgorithm();
-        final List<String> msList = Arrays.asList(msServerAddresses.replace(" ", "").split(","));
         return algorithm.sort(msList, hostIdList, hostId);
     }
 
@@ -119,76 +131,14 @@ public Long getLBPreferredHostCheckInterval(final Long clusterId) {
     }
 
     List<Long> getOrderedHostIdList(final Long dcId) {
-        final List<Long> hostIdList = new ArrayList<>();
-        for (final Host host : getAllAgentBasedHosts()) {
-            if (host.getDataCenterId() == dcId) {
-                hostIdList.add(host.getId());
-            }
-        }
-        Collections.sort(hostIdList, new Comparator<Long>() {
-            @Override
-            public int compare(Long x, Long y) {
-                return Long.compare(x,y);
-            }
-        });
+        final List<Long> hostIdList = getAllAgentBasedHostsFromDB(dcId, null);
+        hostIdList.sort(Comparator.comparingLong(x -> x));
         return hostIdList;
     }
 
-    private List<Host> getAllAgentBasedHosts() {
-        final List<HostVO> allHosts = hostDao.listAll();
-        if (allHosts == null) {
-            return new ArrayList<>();
-        }
-        final List <Host> agentBasedHosts = new ArrayList<>();
-        for (final Host host : allHosts) {
-            conditionallyAddHost(agentBasedHosts, host);
-        }
-        return agentBasedHosts;
-    }
-
-    private void conditionallyAddHost(List<Host> agentBasedHosts, Host host) {
-        if (host == null) {
-            if (logger.isTraceEnabled()) {
-                logger.trace("trying to add no host to a list");
-            }
-            return;
-        }
-
-        EnumSet<ResourceState> allowedStates = EnumSet.of(
-                ResourceState.Enabled,
-                ResourceState.Maintenance,
-                ResourceState.Disabled,
-                ResourceState.ErrorInMaintenance,
-                ResourceState.PrepareForMaintenance);
-        // so the remaining EnumSet<ResourceState> disallowedStates = EnumSet.complementOf(allowedStates)
-        // would be {ResourceState.Creating, ResourceState.Error};
-        if (!allowedStates.contains(host.getResourceState())) {
-            if (logger.isTraceEnabled()) {
-                logger.trace(String.format("host is in '%s' state, not adding to the host list, (id = %s)", host.getResourceState(), host.getUuid()));
-            }
-            return;
-        }
-
-        if (host.getType() != Host.Type.Routing
-                && host.getType() != Host.Type.ConsoleProxy
-                && host.getType() != Host.Type.SecondaryStorage
-                && host.getType() != Host.Type.SecondaryStorageVM) {
-            if (logger.isTraceEnabled()) {
-                logger.trace(String.format("host is of wrong type, not adding to the host list, (id = %s, type = %s)", host.getUuid(), host.getType()));
-            }
-            return;
-        }
-
-        if (host.getHypervisorType() != null
-                && ! (host.getHypervisorType() == Hypervisor.HypervisorType.KVM || host.getHypervisorType() == Hypervisor.HypervisorType.LXC)) {
-
-            if (logger.isTraceEnabled()) {
-                logger.trace(String.format("hypervisor is not the right type, not adding to the host list, (id = %s, hypervisortype = %s)", host.getUuid(), host.getHypervisorType()));
-            }
-            return;
-        }
-
-        agentBasedHosts.add(host);
+    private List<Long> getAllAgentBasedHostsFromDB(final Long zoneId, final Long clusterId) {
+        return hostDao.findHostIdsByZoneClusterResourceStateTypeAndHypervisorType(zoneId, clusterId,
+                agentValidResourceStates, agentValidHostTypes, agentValidHypervisorTypes);
     }
 
     private org.apache.cloudstack.agent.lb.IndirectAgentLBAlgorithm getAgentMSLBAlgorithm() {
@@ -208,18 +158,28 @@ private org.apache.cloudstack.agent.lb.IndirectAgentLBAlgorithm getAgentMSLBAlgo
     public void propagateMSListToAgents() {
         logger.debug("Propagating management server list update to agents");
         final String lbAlgorithm = getLBAlgorithmName();
-        final Map<Long, List<Long>> dcOrderedHostsMap = new HashMap<>();
-        for (final Host host : getAllAgentBasedHosts()) {
-            final Long dcId = host.getDataCenterId();
-            if (!dcOrderedHostsMap.containsKey(dcId)) {
-                dcOrderedHostsMap.put(dcId, getOrderedHostIdList(dcId));
+        List<DataCenterVO> zones = dataCenterDao.listAll();
+        for (DataCenterVO zone : zones) {
+            List<Long> zoneHostIds = new ArrayList<>();
+            Map<Long, List<Long>> clusterHostIdsMap = new HashMap<>();
+            List<Long> clusterIds = clusterDao.listAllClusterIds(zone.getId());
+            for (Long clusterId : clusterIds) {
+                List<Long> hostIds = getAllAgentBasedHostsFromDB(zone.getId(), clusterId);
+                clusterHostIdsMap.put(clusterId, hostIds);
+                zoneHostIds.addAll(hostIds);
             }
-            final List<String> msList = getManagementServerList(host.getId(), host.getDataCenterId(), dcOrderedHostsMap.get(dcId));
-            final Long lbCheckInterval = getLBPreferredHostCheckInterval(host.getClusterId());
-            final SetupMSListCommand cmd = new SetupMSListCommand(msList, lbAlgorithm, lbCheckInterval);
-            final Answer answer = agentManager.easySend(host.getId(), cmd);
-            if (answer == null || !answer.getResult()) {
-                logger.warn(String.format("Failed to setup management servers list to the agent of %s", host));
+            zoneHostIds.sort(Comparator.comparingLong(x -> x));
+            for (Long clusterId : clusterIds) {
+                final Long lbCheckInterval = getLBPreferredHostCheckInterval(clusterId);
+                List<Long> hostIds = clusterHostIdsMap.get(clusterId);
+                for (Long hostId : hostIds) {
+                    final List<String> msList = getManagementServerList(hostId, zone.getId(), zoneHostIds);
+                    final SetupMSListCommand cmd = new SetupMSListCommand(msList, lbAlgorithm, lbCheckInterval);
+                    final Answer answer = agentManager.easySend(hostId, cmd);
+                    if (answer == null || !answer.getResult()) {
+                        logger.warn("Failed to setup management servers list to the agent of ID: {}", hostId);
+                    }
+                }
             }
         }
     }
diff --git a/server/src/main/java/org/apache/cloudstack/agent/lb/algorithm/IndirectAgentLBRoundRobinAlgorithm.java b/server/src/main/java/org/apache/cloudstack/agent/lb/algorithm/IndirectAgentLBRoundRobinAlgorithm.java
index 63fea5e74e6e..49e6899aaeb1 100644
--- a/server/src/main/java/org/apache/cloudstack/agent/lb/algorithm/IndirectAgentLBRoundRobinAlgorithm.java
+++ b/server/src/main/java/org/apache/cloudstack/agent/lb/algorithm/IndirectAgentLBRoundRobinAlgorithm.java
@@ -56,4 +56,9 @@ public String getName() {
     public boolean compare(final List<String> msList, final List<String> receivedMsList) {
         return msList != null && receivedMsList != null && msList.equals(receivedMsList);
     }
+
+    @Override
+    public boolean isHostListNeeded() {
+        return true;
+    }
 }
diff --git a/server/src/main/java/org/apache/cloudstack/outofbandmanagement/OutOfBandManagementServiceImpl.java b/server/src/main/java/org/apache/cloudstack/outofbandmanagement/OutOfBandManagementServiceImpl.java
index 02600b87f290..87c7089c39ff 100644
--- a/server/src/main/java/org/apache/cloudstack/outofbandmanagement/OutOfBandManagementServiceImpl.java
+++ b/server/src/main/java/org/apache/cloudstack/outofbandmanagement/OutOfBandManagementServiceImpl.java
@@ -283,11 +283,11 @@ && isOutOfBandManagementEnabledForCluster(host.getClusterId())
                 && isOutOfBandManagementEnabledForHost(host.getId());
     }
 
-    public boolean transitionPowerStateToDisabled(List<? extends Host> hosts) {
+    public boolean transitionPowerStateToDisabled(List<Long> hostIds) {
         boolean result = true;
-        for (Host host : hosts) {
+        for (Long hostId : hostIds) {
             result = result && transitionPowerState(OutOfBandManagement.PowerState.Event.Disabled,
-                    outOfBandManagementDao.findByHost(host.getId()));
+                    outOfBandManagementDao.findByHost(hostId));
         }
         return result;
     }
@@ -316,7 +316,7 @@ public OutOfBandManagementResponse enableOutOfBandManagement(final DataCenter zo
     @ActionEvent(eventType = EventTypes.EVENT_HOST_OUTOFBAND_MANAGEMENT_DISABLE, eventDescription = "disabling out-of-band management on a zone")
     public OutOfBandManagementResponse disableOutOfBandManagement(final DataCenter zone) {
         dataCenterDetailsDao.persist(zone.getId(), OOBM_ENABLED_DETAIL, String.valueOf(false));
-        transitionPowerStateToDisabled(hostDao.findByDataCenterId(zone.getId()));
+        transitionPowerStateToDisabled(hostDao.listIdsByDataCenterId(zone.getId()));
 
         return buildEnableDisableResponse(false);
     }
@@ -332,7 +332,7 @@ public OutOfBandManagementResponse enableOutOfBandManagement(final Cluster clust
     @ActionEvent(eventType = EventTypes.EVENT_HOST_OUTOFBAND_MANAGEMENT_DISABLE, eventDescription = "disabling out-of-band management on a cluster")
     public OutOfBandManagementResponse disableOutOfBandManagement(final Cluster cluster) {
         clusterDetailsDao.persist(cluster.getId(), OOBM_ENABLED_DETAIL, String.valueOf(false));
-        transitionPowerStateToDisabled(hostDao.findByClusterId(cluster.getId()));
+        transitionPowerStateToDisabled(hostDao.listIdsByClusterId(cluster.getId()));
         return buildEnableDisableResponse(false);
     }
 
@@ -352,7 +352,7 @@ public OutOfBandManagementResponse enableOutOfBandManagement(final Host host) {
         outOfBandManagementConfig.setEnabled(true);
         boolean updateResult = outOfBandManagementDao.update(outOfBandManagementConfig.getId(), (OutOfBandManagementVO) outOfBandManagementConfig);
         if (updateResult) {
-            transitionPowerStateToDisabled(Collections.singletonList(host));
+            transitionPowerStateToDisabled(Collections.singletonList(host.getId()));
         }
         return buildEnableDisableResponse(true);
     }
@@ -365,7 +365,7 @@ public OutOfBandManagementResponse disableOutOfBandManagement(final Host host) {
         outOfBandManagementConfig.setEnabled(false);
         boolean updateResult = outOfBandManagementDao.update(outOfBandManagementConfig.getId(), (OutOfBandManagementVO) outOfBandManagementConfig);
         if (updateResult) {
-            transitionPowerStateToDisabled(Collections.singletonList(host));
+            transitionPowerStateToDisabled(Collections.singletonList(host.getId()));
         }
         return buildEnableDisableResponse(false);
     }
@@ -576,10 +576,8 @@ protected void runInContext() {
                     if (isOutOfBandManagementEnabled(host)) {
                         submitBackgroundPowerSyncTask(host);
                     } else if (outOfBandManagementHost.getPowerState() != OutOfBandManagement.PowerState.Disabled) {
-                        if (transitionPowerStateToDisabled(Collections.singletonList(host))) {
-                            if (logger.isDebugEnabled()) {
-                                logger.debug(String.format("Out-of-band management was disabled in zone/cluster/host, disabled power state for %s", host));
-                            }
+                        if (transitionPowerStateToDisabled(Collections.singletonList(host.getId()))) {
+                            logger.debug("Out-of-band management was disabled in zone/cluster/host, disabled power state for {}", host);
                         }
                     }
                 }
diff --git a/server/src/test/java/com/cloud/configuration/ConfigurationManagerTest.java b/server/src/test/java/com/cloud/configuration/ConfigurationManagerTest.java
index 4ae871e1ba58..b0035265da2a 100644
--- a/server/src/test/java/com/cloud/configuration/ConfigurationManagerTest.java
+++ b/server/src/test/java/com/cloud/configuration/ConfigurationManagerTest.java
@@ -826,7 +826,7 @@ public void checkIfPodIsDeletableFailureOnClusterTest() {
 
     @Test
     public void checkIfZoneIsDeletableSuccessTest() {
-        Mockito.when(_hostDao.listByDataCenterId(anyLong())).thenReturn(new ArrayList<HostVO>());
+        Mockito.when(_hostDao.listEnabledIdsByDataCenterId(anyLong())).thenReturn(new ArrayList<>());
         Mockito.when(_podDao.listByDataCenterId(anyLong())).thenReturn(new ArrayList<HostPodVO>());
         Mockito.when(_privateIpAddressDao.countIPs(anyLong(), anyBoolean())).thenReturn(0);
         Mockito.when(_publicIpAddressDao.countIPs(anyLong(), anyBoolean())).thenReturn(0);
@@ -840,11 +840,7 @@ public void checkIfZoneIsDeletableSuccessTest() {
 
     @Test(expected = CloudRuntimeException.class)
     public void checkIfZoneIsDeletableFailureOnHostTest() {
-        HostVO hostVO = Mockito.mock(HostVO.class);
-        ArrayList<HostVO> arrayList = new ArrayList<HostVO>();
-        arrayList.add(hostVO);
-
-        Mockito.when(_hostDao.listByDataCenterId(anyLong())).thenReturn(arrayList);
+        Mockito.when(_hostDao.listEnabledIdsByDataCenterId(anyLong())).thenReturn(List.of(1L));
         Mockito.when(_podDao.listByDataCenterId(anyLong())).thenReturn(new ArrayList<HostPodVO>());
         Mockito.when(_privateIpAddressDao.countIPs(anyLong(), anyBoolean())).thenReturn(0);
         Mockito.when(_publicIpAddressDao.countIPs(anyLong(), anyBoolean())).thenReturn(0);
@@ -862,7 +858,7 @@ public void checkIfZoneIsDeletableFailureOnPodTest() {
         ArrayList<HostPodVO> arrayList = new ArrayList<HostPodVO>();
         arrayList.add(hostPodVO);
 
-        Mockito.when(_hostDao.listByDataCenterId(anyLong())).thenReturn(new ArrayList<HostVO>());
+        Mockito.when(_hostDao.listEnabledIdsByDataCenterId(anyLong())).thenReturn(new ArrayList<>());
         Mockito.when(_podDao.listByDataCenterId(anyLong())).thenReturn(arrayList);
         Mockito.when(_privateIpAddressDao.countIPs(anyLong(), anyBoolean())).thenReturn(0);
         Mockito.when(_publicIpAddressDao.countIPs(anyLong(), anyBoolean())).thenReturn(0);
@@ -876,7 +872,7 @@ public void checkIfZoneIsDeletableFailureOnPodTest() {
 
     @Test(expected = CloudRuntimeException.class)
     public void checkIfZoneIsDeletableFailureOnPrivateIpAddressTest() {
-        Mockito.when(_hostDao.listByDataCenterId(anyLong())).thenReturn(new ArrayList<HostVO>());
+        Mockito.when(_hostDao.listEnabledIdsByDataCenterId(anyLong())).thenReturn(new ArrayList<>());
         Mockito.when(_podDao.listByDataCenterId(anyLong())).thenReturn(new ArrayList<HostPodVO>());
         Mockito.when(_privateIpAddressDao.countIPs(anyLong(), anyBoolean())).thenReturn(1);
         Mockito.when(_publicIpAddressDao.countIPs(anyLong(), anyBoolean())).thenReturn(0);
@@ -890,7 +886,7 @@ public void checkIfZoneIsDeletableFailureOnPrivateIpAddressTest() {
 
     @Test(expected = CloudRuntimeException.class)
     public void checkIfZoneIsDeletableFailureOnPublicIpAddressTest() {
-        Mockito.when(_hostDao.listByDataCenterId(anyLong())).thenReturn(new ArrayList<HostVO>());
+        Mockito.when(_hostDao.listEnabledIdsByDataCenterId(anyLong())).thenReturn(new ArrayList<>());
         Mockito.when(_podDao.listByDataCenterId(anyLong())).thenReturn(new ArrayList<HostPodVO>());
         Mockito.when(_privateIpAddressDao.countIPs(anyLong(), anyBoolean())).thenReturn(0);
         Mockito.when(_publicIpAddressDao.countIPs(anyLong(), anyBoolean())).thenReturn(1);
@@ -908,7 +904,7 @@ public void checkIfZoneIsDeletableFailureOnVmInstanceTest() {
         ArrayList<VMInstanceVO> arrayList = new ArrayList<VMInstanceVO>();
         arrayList.add(vMInstanceVO);
 
-        Mockito.when(_hostDao.listByDataCenterId(anyLong())).thenReturn(new ArrayList<HostVO>());
+        Mockito.when(_hostDao.listEnabledIdsByDataCenterId(anyLong())).thenReturn(new ArrayList<>());
         Mockito.when(_podDao.listByDataCenterId(anyLong())).thenReturn(new ArrayList<HostPodVO>());
         Mockito.when(_privateIpAddressDao.countIPs(anyLong(), anyBoolean())).thenReturn(0);
         Mockito.when(_publicIpAddressDao.countIPs(anyLong(), anyBoolean())).thenReturn(0);
@@ -926,7 +922,7 @@ public void checkIfZoneIsDeletableFailureOnVolumeTest() {
         ArrayList<VolumeVO> arrayList = new ArrayList<VolumeVO>();
         arrayList.add(volumeVO);
 
-        Mockito.when(_hostDao.listByDataCenterId(anyLong())).thenReturn(new ArrayList<HostVO>());
+        Mockito.when(_hostDao.listEnabledIdsByDataCenterId(anyLong())).thenReturn(new ArrayList<>());
         Mockito.when(_podDao.listByDataCenterId(anyLong())).thenReturn(new ArrayList<HostPodVO>());
         Mockito.when(_privateIpAddressDao.countIPs(anyLong(), anyBoolean())).thenReturn(0);
         Mockito.when(_publicIpAddressDao.countIPs(anyLong(), anyBoolean())).thenReturn(0);
@@ -944,7 +940,7 @@ public void checkIfZoneIsDeletableFailureOnPhysicalNetworkTest() {
         ArrayList<PhysicalNetworkVO> arrayList = new ArrayList<PhysicalNetworkVO>();
         arrayList.add(physicalNetworkVO);
 
-        Mockito.when(_hostDao.listByDataCenterId(anyLong())).thenReturn(new ArrayList<HostVO>());
+        Mockito.when(_hostDao.listEnabledIdsByDataCenterId(anyLong())).thenReturn(new ArrayList<>());
         Mockito.when(_podDao.listByDataCenterId(anyLong())).thenReturn(new ArrayList<HostPodVO>());
         Mockito.when(_privateIpAddressDao.countIPs(anyLong(), anyBoolean())).thenReturn(0);
         Mockito.when(_publicIpAddressDao.countIPs(anyLong(), anyBoolean())).thenReturn(0);
diff --git a/server/src/test/java/com/cloud/deploy/DeploymentPlanningManagerImplTest.java b/server/src/test/java/com/cloud/deploy/DeploymentPlanningManagerImplTest.java
index 482d17908f43..c197a57b1095 100644
--- a/server/src/test/java/com/cloud/deploy/DeploymentPlanningManagerImplTest.java
+++ b/server/src/test/java/com/cloud/deploy/DeploymentPlanningManagerImplTest.java
@@ -889,7 +889,7 @@ private DeploymentClusterPlanner setupMocksForPlanDeploymentHostTests(HostVO hos
         Pair<Host, Map<Volume, StoragePool>> potentialResources = new Pair<>(host, suitableVolumeStoragePoolMap);
 
         Mockito.when(capacityMgr.checkIfHostReachMaxGuestLimit(host)).thenReturn(false);
-        Mockito.when(capacityMgr.checkIfHostHasCpuCapability(ArgumentMatchers.anyLong(), ArgumentMatchers.anyInt(), ArgumentMatchers.anyInt())).thenReturn(true);
+        Mockito.when(capacityMgr.checkIfHostHasCpuCapability(ArgumentMatchers.any(Host.class), ArgumentMatchers.anyInt(), ArgumentMatchers.anyInt())).thenReturn(true);
         Mockito.when(capacityMgr.checkIfHostHasCapacity(
                 ArgumentMatchers.anyLong(),
                 ArgumentMatchers.anyInt(),
@@ -1218,7 +1218,7 @@ private List<Long> prepareMockForAvoidOtherClustersForDeploymentIfMigrationDisab
             throw new RuntimeException(e);
         }
         List<Long> allClusters = List.of(101L, 102L, 103L, 104L);
-        Mockito.when(_clusterDao.listAllClusters(Mockito.anyLong())).thenReturn(allClusters);
+        Mockito.when(_clusterDao.listAllClusterIds(Mockito.anyLong())).thenReturn(allClusters);
         if (mockVolumes) {
             VolumeVO vol1 = Mockito.mock(VolumeVO.class);
             Mockito.when(vol1.getPoolId()).thenReturn(1L);
diff --git a/server/src/test/java/com/cloud/network/Ipv6ServiceImplTest.java b/server/src/test/java/com/cloud/network/Ipv6ServiceImplTest.java
index 02ddd0c983ef..a75d26f10622 100644
--- a/server/src/test/java/com/cloud/network/Ipv6ServiceImplTest.java
+++ b/server/src/test/java/com/cloud/network/Ipv6ServiceImplTest.java
@@ -16,6 +16,38 @@
 // under the License.
 package com.cloud.network;
 
+import java.net.URI;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Iterator;
+import java.util.List;
+import java.util.UUID;
+
+import javax.management.InstanceAlreadyExistsException;
+import javax.management.MBeanRegistrationException;
+import javax.management.MalformedObjectNameException;
+import javax.management.NotCompliantMBeanException;
+
+import org.apache.cloudstack.api.command.user.ipv6.CreateIpv6FirewallRuleCmd;
+import org.apache.cloudstack.api.command.user.ipv6.UpdateIpv6FirewallRuleCmd;
+import org.apache.cloudstack.api.response.Ipv6RouteResponse;
+import org.apache.cloudstack.api.response.VpcResponse;
+import org.apache.cloudstack.context.CallContext;
+import org.apache.cloudstack.engine.orchestration.service.NetworkOrchestrationService;
+import org.apache.commons.collections.CollectionUtils;
+import org.junit.After;
+import org.junit.Assert;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.InjectMocks;
+import org.mockito.Mock;
+import org.mockito.MockedStatic;
+import org.mockito.Mockito;
+import org.mockito.MockitoAnnotations;
+import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.stubbing.Answer;
+
 import com.cloud.api.ApiDBUtils;
 import com.cloud.dc.DataCenter;
 import com.cloud.dc.DataCenterGuestIpv6PrefixVO;
@@ -61,36 +93,6 @@
 import com.cloud.vm.dao.NicDao;
 import com.googlecode.ipv6.IPv6Network;
 import com.googlecode.ipv6.IPv6NetworkMask;
-import org.apache.cloudstack.api.command.user.ipv6.CreateIpv6FirewallRuleCmd;
-import org.apache.cloudstack.api.command.user.ipv6.UpdateIpv6FirewallRuleCmd;
-import org.apache.cloudstack.api.response.Ipv6RouteResponse;
-import org.apache.cloudstack.api.response.VpcResponse;
-import org.apache.cloudstack.context.CallContext;
-import org.apache.cloudstack.engine.orchestration.service.NetworkOrchestrationService;
-import org.apache.commons.collections.CollectionUtils;
-import org.junit.After;
-import org.junit.Assert;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.mockito.InjectMocks;
-import org.mockito.Mock;
-import org.mockito.MockedStatic;
-import org.mockito.Mockito;
-import org.mockito.MockitoAnnotations;
-import org.mockito.junit.MockitoJUnitRunner;
-import org.mockito.stubbing.Answer;
-
-import javax.management.InstanceAlreadyExistsException;
-import javax.management.MBeanRegistrationException;
-import javax.management.MalformedObjectNameException;
-import javax.management.NotCompliantMBeanException;
-import java.net.URI;
-import java.util.ArrayList;
-import java.util.Arrays;
-import java.util.Iterator;
-import java.util.List;
-import java.util.UUID;
 
 @RunWith(MockitoJUnitRunner.class)
 public class Ipv6ServiceImplTest {
diff --git a/server/src/test/java/com/cloud/network/NetworkServiceImplTest.java b/server/src/test/java/com/cloud/network/NetworkServiceImplTest.java
index 64d813c9ba8b..f968140e1906 100644
--- a/server/src/test/java/com/cloud/network/NetworkServiceImplTest.java
+++ b/server/src/test/java/com/cloud/network/NetworkServiceImplTest.java
@@ -22,10 +22,10 @@
 import static org.mockito.ArgumentMatchers.eq;
 import static org.mockito.ArgumentMatchers.nullable;
 import static org.mockito.Mockito.doNothing;
+import static org.mockito.Mockito.doReturn;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.times;
 import static org.mockito.Mockito.when;
-import static org.mockito.Mockito.doReturn;
 
 import java.lang.reflect.Field;
 import java.util.ArrayList;
@@ -36,15 +36,6 @@
 import java.util.Map;
 import java.util.UUID;
 
-import com.cloud.domain.Domain;
-import com.cloud.domain.DomainVO;
-import com.cloud.domain.dao.DomainDao;
-import com.cloud.network.dao.NsxProviderDao;
-import com.cloud.network.dao.PublicIpQuarantineDao;
-import com.cloud.network.vo.PublicIpQuarantineVO;
-import com.cloud.user.dao.AccountDao;
-import com.cloud.utils.net.Ip;
-import com.cloud.exception.InsufficientAddressCapacityException;
 import org.apache.cloudstack.alert.AlertService;
 import org.apache.cloudstack.api.command.user.address.UpdateQuarantinedIpCmd;
 import org.apache.cloudstack.api.command.user.network.CreateNetworkCmd;
@@ -53,6 +44,7 @@
 import org.apache.cloudstack.engine.orchestration.service.NetworkOrchestrationService;
 import org.apache.cloudstack.framework.config.ConfigKey;
 import org.apache.cloudstack.network.RoutedIpv4Manager;
+import org.junit.After;
 import org.junit.Assert;
 import org.junit.Before;
 import org.junit.BeforeClass;
@@ -61,8 +53,10 @@
 import org.mockito.ArgumentMatchers;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
+import org.mockito.MockedStatic;
 import org.mockito.Mockito;
 import org.mockito.MockitoAnnotations;
+import org.mockito.junit.MockitoJUnitRunner;
 import org.springframework.test.util.ReflectionTestUtils;
 
 import com.cloud.agent.api.to.IpAddressTO;
@@ -72,6 +66,10 @@
 import com.cloud.dc.DataCenter;
 import com.cloud.dc.DataCenterVO;
 import com.cloud.dc.dao.DataCenterDao;
+import com.cloud.domain.Domain;
+import com.cloud.domain.DomainVO;
+import com.cloud.domain.dao.DomainDao;
+import com.cloud.exception.InsufficientAddressCapacityException;
 import com.cloud.exception.InsufficientCapacityException;
 import com.cloud.exception.InvalidParameterValueException;
 import com.cloud.exception.ResourceAllocationException;
@@ -79,10 +77,13 @@
 import com.cloud.network.dao.IPAddressVO;
 import com.cloud.network.dao.NetworkDao;
 import com.cloud.network.dao.NetworkVO;
+import com.cloud.network.dao.NsxProviderDao;
 import com.cloud.network.dao.PhysicalNetworkDao;
 import com.cloud.network.dao.PhysicalNetworkVO;
+import com.cloud.network.dao.PublicIpQuarantineDao;
 import com.cloud.network.router.CommandSetupHelper;
 import com.cloud.network.router.NetworkHelper;
+import com.cloud.network.vo.PublicIpQuarantineVO;
 import com.cloud.network.vpc.VpcManager;
 import com.cloud.network.vpc.VpcVO;
 import com.cloud.network.vpc.dao.VpcDao;
@@ -100,18 +101,17 @@
 import com.cloud.user.AccountVO;
 import com.cloud.user.User;
 import com.cloud.user.UserVO;
+import com.cloud.user.dao.AccountDao;
 import com.cloud.user.dao.UserDao;
 import com.cloud.utils.Pair;
 import com.cloud.utils.db.EntityManager;
 import com.cloud.utils.exception.CloudRuntimeException;
+import com.cloud.utils.net.Ip;
 import com.cloud.vm.DomainRouterVO;
 import com.cloud.vm.NicVO;
 import com.cloud.vm.VirtualMachine;
 import com.cloud.vm.dao.DomainRouterDao;
 import com.cloud.vm.dao.NicDao;
-import org.junit.After;
-import org.mockito.MockedStatic;
-import org.mockito.junit.MockitoJUnitRunner;
 
 @RunWith(MockitoJUnitRunner.class)
 public class NetworkServiceImplTest {
diff --git a/server/src/test/java/com/cloud/network/as/AutoScaleManagerImplTest.java b/server/src/test/java/com/cloud/network/as/AutoScaleManagerImplTest.java
index b391aeb9f076..282d6362d396 100644
--- a/server/src/test/java/com/cloud/network/as/AutoScaleManagerImplTest.java
+++ b/server/src/test/java/com/cloud/network/as/AutoScaleManagerImplTest.java
@@ -16,6 +16,66 @@
 // under the License.
 package com.cloud.network.as;
 
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.ArgumentMatchers.anyList;
+import static org.mockito.ArgumentMatchers.anyLong;
+import static org.mockito.ArgumentMatchers.anyString;
+import static org.mockito.ArgumentMatchers.eq;
+import static org.mockito.ArgumentMatchers.matches;
+import static org.mockito.ArgumentMatchers.nullable;
+import static org.mockito.Mockito.never;
+import static org.mockito.Mockito.times;
+import static org.mockito.Mockito.when;
+
+import java.lang.reflect.Field;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.Date;
+import java.util.HashMap;
+import java.util.LinkedHashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.UUID;
+import java.util.concurrent.CompletionService;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.Executors;
+import java.util.concurrent.Future;
+import java.util.concurrent.ScheduledExecutorService;
+
+import org.apache.cloudstack.affinity.AffinityGroupVO;
+import org.apache.cloudstack.affinity.dao.AffinityGroupDao;
+import org.apache.cloudstack.annotation.AnnotationService;
+import org.apache.cloudstack.annotation.dao.AnnotationDao;
+import org.apache.cloudstack.api.ApiConstants;
+import org.apache.cloudstack.api.BaseCmd;
+import org.apache.cloudstack.api.command.admin.autoscale.CreateCounterCmd;
+import org.apache.cloudstack.api.command.user.autoscale.CreateAutoScalePolicyCmd;
+import org.apache.cloudstack.api.command.user.autoscale.CreateAutoScaleVmGroupCmd;
+import org.apache.cloudstack.api.command.user.autoscale.CreateAutoScaleVmProfileCmd;
+import org.apache.cloudstack.api.command.user.autoscale.CreateConditionCmd;
+import org.apache.cloudstack.api.command.user.autoscale.ListCountersCmd;
+import org.apache.cloudstack.api.command.user.autoscale.UpdateAutoScaleVmGroupCmd;
+import org.apache.cloudstack.api.command.user.autoscale.UpdateAutoScaleVmProfileCmd;
+import org.apache.cloudstack.api.command.user.autoscale.UpdateConditionCmd;
+import org.apache.cloudstack.api.command.user.vm.DeployVMCmd;
+import org.apache.cloudstack.config.ApiServiceConfiguration;
+import org.apache.cloudstack.context.CallContext;
+import org.apache.cloudstack.framework.config.ConfigKey;
+import org.apache.cloudstack.userdata.UserDataManager;
+import org.junit.After;
+import org.junit.Assert;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.InjectMocks;
+import org.mockito.Mock;
+import org.mockito.MockedStatic;
+import org.mockito.Mockito;
+import org.mockito.Spy;
+import org.mockito.junit.MockitoJUnitRunner;
+import org.springframework.test.util.ReflectionTestUtils;
+
 import com.cloud.agent.AgentManager;
 import com.cloud.agent.api.PerformanceMonitorAnswer;
 import com.cloud.agent.api.PerformanceMonitorCommand;
@@ -39,6 +99,7 @@
 import com.cloud.exception.ResourceAllocationException;
 import com.cloud.exception.ResourceInUseException;
 import com.cloud.exception.ResourceUnavailableException;
+import com.cloud.host.Host;
 import com.cloud.host.HostVO;
 import com.cloud.host.dao.HostDao;
 import com.cloud.network.Network;
@@ -104,65 +165,6 @@
 import com.cloud.vm.dao.DomainRouterDao;
 import com.cloud.vm.dao.UserVmDao;
 import com.cloud.vm.dao.VMInstanceDao;
-import org.apache.cloudstack.affinity.AffinityGroupVO;
-import org.apache.cloudstack.affinity.dao.AffinityGroupDao;
-import org.apache.cloudstack.annotation.AnnotationService;
-import org.apache.cloudstack.annotation.dao.AnnotationDao;
-import org.apache.cloudstack.api.ApiConstants;
-import org.apache.cloudstack.api.BaseCmd;
-import org.apache.cloudstack.api.command.admin.autoscale.CreateCounterCmd;
-import org.apache.cloudstack.api.command.user.autoscale.CreateAutoScalePolicyCmd;
-import org.apache.cloudstack.api.command.user.autoscale.CreateAutoScaleVmGroupCmd;
-import org.apache.cloudstack.api.command.user.autoscale.CreateAutoScaleVmProfileCmd;
-import org.apache.cloudstack.api.command.user.autoscale.CreateConditionCmd;
-import org.apache.cloudstack.api.command.user.autoscale.ListCountersCmd;
-import org.apache.cloudstack.api.command.user.autoscale.UpdateAutoScaleVmGroupCmd;
-import org.apache.cloudstack.api.command.user.autoscale.UpdateAutoScaleVmProfileCmd;
-import org.apache.cloudstack.api.command.user.autoscale.UpdateConditionCmd;
-import org.apache.cloudstack.api.command.user.vm.DeployVMCmd;
-import org.apache.cloudstack.config.ApiServiceConfiguration;
-import org.apache.cloudstack.context.CallContext;
-import org.apache.cloudstack.framework.config.ConfigKey;
-import org.apache.cloudstack.userdata.UserDataManager;
-import org.junit.After;
-import org.junit.Assert;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.mockito.InjectMocks;
-import org.mockito.Mock;
-import org.mockito.MockedStatic;
-import org.mockito.Mockito;
-import org.mockito.Spy;
-import org.mockito.junit.MockitoJUnitRunner;
-import org.springframework.test.util.ReflectionTestUtils;
-
-import java.lang.reflect.Field;
-import java.util.ArrayList;
-import java.util.Arrays;
-import java.util.Collections;
-import java.util.Date;
-import java.util.HashMap;
-import java.util.LinkedHashMap;
-import java.util.List;
-import java.util.Map;
-import java.util.UUID;
-import java.util.concurrent.CompletionService;
-import java.util.concurrent.ExecutionException;
-import java.util.concurrent.Executors;
-import java.util.concurrent.Future;
-import java.util.concurrent.ScheduledExecutorService;
-
-import static org.mockito.ArgumentMatchers.any;
-import static org.mockito.ArgumentMatchers.anyList;
-import static org.mockito.ArgumentMatchers.anyLong;
-import static org.mockito.ArgumentMatchers.anyString;
-import static org.mockito.ArgumentMatchers.eq;
-import static org.mockito.ArgumentMatchers.matches;
-import static org.mockito.ArgumentMatchers.nullable;
-import static org.mockito.Mockito.never;
-import static org.mockito.Mockito.times;
-import static org.mockito.Mockito.when;
 
 @RunWith(MockitoJUnitRunner.class)
 public class AutoScaleManagerImplTest {
@@ -2246,12 +2248,14 @@ public void getVmStatsFromHosts() {
     @Test
     public void getVmStatsByIdFromHost() {
         List<Long> vmIds = Mockito.mock(ArrayList.class);
+        Map<Long, VmStatsEntry> vmStatsById = Mockito.mock(HashMap.class);
+        Mockito.doReturn(vmStatsById).when(virtualMachineManager).getVirtualMachineStatistics(Mockito.any(Host.class), anyList());
 
         Map<Long, ? extends VmStats> result = autoScaleManagerImplSpy.getVmStatsByIdFromHost(-1L, vmIds);
 
         Assert.assertEquals(0, result.size());
 
-        Mockito.verify(virtualMachineManager, never()).getVirtualMachineStatistics(anyLong(), anyString(), anyList());
+        Mockito.verify(virtualMachineManager, never()).getVirtualMachineStatistics(Mockito.any(Host.class), anyList());
     }
 
     @Test
@@ -2263,13 +2267,13 @@ public void getVmStatsByIdFromHost2() {
         when(hostDao.findById(hostId)).thenReturn(hostMock);
         when(hostMock.getId()).thenReturn(hostId);
         when(hostMock.getName()).thenReturn(hostName);
-        Mockito.doReturn(vmStatsById).when(virtualMachineManager).getVirtualMachineStatistics(anyLong(), anyString(), anyList());
+        Mockito.doReturn(vmStatsById).when(virtualMachineManager).getVirtualMachineStatistics(Mockito.any(Host.class), anyList());
 
         Map<Long, ? extends VmStats> result = autoScaleManagerImplSpy.getVmStatsByIdFromHost(hostId, vmIds);
 
         Assert.assertEquals(vmStatsById, result);
 
-        Mockito.verify(virtualMachineManager).getVirtualMachineStatistics(anyLong(), anyString(), anyList());
+        Mockito.verify(virtualMachineManager).getVirtualMachineStatistics(Mockito.any(Host.class), anyList());
     }
 
     @Test
diff --git a/server/src/test/java/com/cloud/resource/MockResourceManagerImpl.java b/server/src/test/java/com/cloud/resource/MockResourceManagerImpl.java
index 6aae7a091d3f..3de39fa21e6b 100755
--- a/server/src/test/java/com/cloud/resource/MockResourceManagerImpl.java
+++ b/server/src/test/java/com/cloud/resource/MockResourceManagerImpl.java
@@ -446,7 +446,7 @@ public List<HostVO> listAllHostsInOneZoneNotInClusterByHypervisors(List<Hypervis
      * @see com.cloud.resource.ResourceManager#listAvailHypervisorInZone(java.lang.Long, java.lang.Long)
      */
     @Override
-    public List<HypervisorType> listAvailHypervisorInZone(final Long hostId, final Long zoneId) {
+    public List<HypervisorType> listAvailHypervisorInZone(final Long zoneId) {
         // TODO Auto-generated method stub
         return null;
     }
@@ -473,7 +473,7 @@ public HostVO findHostByName(final String name) {
      * @see com.cloud.resource.ResourceManager#getHostStatistics(long)
      */
     @Override
-    public HostStats getHostStatistics(final long hostId) {
+    public HostStats getHostStatistics(final Host host) {
         // TODO Auto-generated method stub
         return null;
     }
diff --git a/server/src/test/java/com/cloud/resourcelimit/ResourceLimitManagerImplTest.java b/server/src/test/java/com/cloud/resourcelimit/ResourceLimitManagerImplTest.java
index defcd09b1744..34030626d22e 100644
--- a/server/src/test/java/com/cloud/resourcelimit/ResourceLimitManagerImplTest.java
+++ b/server/src/test/java/com/cloud/resourcelimit/ResourceLimitManagerImplTest.java
@@ -59,10 +59,8 @@
 import com.cloud.offering.ServiceOffering;
 import com.cloud.projects.ProjectVO;
 import com.cloud.projects.dao.ProjectDao;
-import com.cloud.service.ServiceOfferingVO;
 import com.cloud.service.dao.ServiceOfferingDao;
 import com.cloud.storage.DiskOfferingVO;
-import com.cloud.storage.VMTemplateVO;
 import com.cloud.storage.VolumeVO;
 import com.cloud.storage.dao.DiskOfferingDao;
 import com.cloud.storage.dao.VMTemplateDao;
@@ -715,8 +713,8 @@ public void testGetVmsWithAccountAndTagNoTag() throws NoSuchFieldException, Ille
     @Test
     public void testGetVmsWithAccountAndTagNegative() {
         String tag = hostTags.get(0);
-        Mockito.when(serviceOfferingDao.listByHostTag(tag)).thenReturn(null);
-        Mockito.when(vmTemplateDao.listByTemplateTag(tag)).thenReturn(null);
+        Mockito.when(serviceOfferingDao.listIdsByHostTag(tag)).thenReturn(null);
+        Mockito.when(vmTemplateDao.listIdsByTemplateTag(tag)).thenReturn(null);
         List<UserVmJoinVO> result = resourceLimitManager.getVmsWithAccountAndTag(1L, hostTags.get(0));
         Assert.assertTrue(CollectionUtils.isEmpty(result));
     }
@@ -725,12 +723,8 @@ public void testGetVmsWithAccountAndTagNegative() {
     public void testGetVmsWithAccountAndTag() throws NoSuchFieldException, IllegalAccessException {
         overrideDefaultConfigValue(VirtualMachineManager.ResourceCountRunningVMsonly, "_defaultValue", "true");
         String tag = hostTags.get(0);
-        ServiceOfferingVO serviceOfferingVO = Mockito.mock(ServiceOfferingVO.class);
-        Mockito.when(serviceOfferingVO.getId()).thenReturn(1L);
-        VMTemplateVO templateVO = Mockito.mock(VMTemplateVO.class);
-        Mockito.when(templateVO.getId()).thenReturn(1L);
-        Mockito.when(serviceOfferingDao.listByHostTag(tag)).thenReturn(List.of(serviceOfferingVO));
-        Mockito.when(vmTemplateDao.listByTemplateTag(tag)).thenReturn(List.of(templateVO));
+        Mockito.when(serviceOfferingDao.listIdsByHostTag(tag)).thenReturn(List.of(1L));
+        Mockito.when(vmTemplateDao.listIdsByTemplateTag(tag)).thenReturn(List.of(1L));
         List<UserVmJoinVO> vmList = List.of(Mockito.mock(UserVmJoinVO.class));
         Mockito.when(userVmJoinDao.listByAccountServiceOfferingTemplateAndNotInState(Mockito.anyLong(), Mockito.anyList(), Mockito.anyList(), Mockito.anyList())).thenReturn(vmList);
         List<UserVmJoinVO> result = resourceLimitManager.getVmsWithAccountAndTag(1L, tag);
diff --git a/server/src/test/java/com/cloud/user/DomainManagerImplTest.java b/server/src/test/java/com/cloud/user/DomainManagerImplTest.java
index 39155986941e..2c2fb5d5f93b 100644
--- a/server/src/test/java/com/cloud/user/DomainManagerImplTest.java
+++ b/server/src/test/java/com/cloud/user/DomainManagerImplTest.java
@@ -17,6 +17,30 @@
 
 package com.cloud.user;
 
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+import java.util.UUID;
+
+import org.apache.cloudstack.annotation.dao.AnnotationDao;
+import org.apache.cloudstack.context.CallContext;
+import org.apache.cloudstack.engine.orchestration.service.NetworkOrchestrationService;
+import org.apache.cloudstack.framework.messagebus.MessageBus;
+import org.apache.cloudstack.framework.messagebus.PublishScope;
+import org.apache.cloudstack.network.RoutedIpv4Manager;
+import org.apache.cloudstack.region.RegionManager;
+import org.junit.Assert;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.ArgumentMatchers;
+import org.mockito.InjectMocks;
+import org.mockito.Mock;
+import org.mockito.MockedStatic;
+import org.mockito.Mockito;
+import org.mockito.Spy;
+import org.mockito.junit.MockitoJUnitRunner;
+
 import com.cloud.api.query.dao.DiskOfferingJoinDao;
 import com.cloud.api.query.dao.NetworkOfferingJoinDao;
 import com.cloud.api.query.dao.ServiceOfferingJoinDao;
@@ -44,29 +68,6 @@
 import com.cloud.utils.db.SearchCriteria;
 import com.cloud.utils.exception.CloudRuntimeException;
 import com.cloud.utils.net.NetUtils;
-import org.apache.cloudstack.annotation.dao.AnnotationDao;
-import org.apache.cloudstack.context.CallContext;
-import org.apache.cloudstack.engine.orchestration.service.NetworkOrchestrationService;
-import org.apache.cloudstack.framework.messagebus.MessageBus;
-import org.apache.cloudstack.framework.messagebus.PublishScope;
-import org.apache.cloudstack.network.RoutedIpv4Manager;
-import org.apache.cloudstack.region.RegionManager;
-import org.junit.Assert;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.mockito.InjectMocks;
-import org.mockito.ArgumentMatchers;
-import org.mockito.Mock;
-import org.mockito.MockedStatic;
-import org.mockito.Mockito;
-import org.mockito.Spy;
-import org.mockito.junit.MockitoJUnitRunner;
-
-import java.util.ArrayList;
-import java.util.Collections;
-import java.util.List;
-import java.util.UUID;
 
 
 @RunWith(MockitoJUnitRunner.class)
diff --git a/server/src/test/java/org/apache/cloudstack/agent/lb/IndirectAgentLBServiceImplTest.java b/server/src/test/java/org/apache/cloudstack/agent/lb/IndirectAgentLBServiceImplTest.java
index 2f0c1c3185cd..0c0097393cae 100644
--- a/server/src/test/java/org/apache/cloudstack/agent/lb/IndirectAgentLBServiceImplTest.java
+++ b/server/src/test/java/org/apache/cloudstack/agent/lb/IndirectAgentLBServiceImplTest.java
@@ -16,13 +16,17 @@
 // under the License.
 package org.apache.cloudstack.agent.lb;
 
-import com.cloud.agent.AgentManager;
-import com.cloud.host.Host;
-import com.cloud.host.HostVO;
-import com.cloud.host.dao.HostDao;
-import com.cloud.hypervisor.Hypervisor;
-import com.cloud.resource.ResourceState;
-import com.cloud.utils.exception.CloudRuntimeException;
+import static org.mockito.Mockito.doReturn;
+import static org.mockito.Mockito.when;
+
+import java.lang.reflect.Field;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.HashSet;
+import java.util.List;
+import java.util.stream.Collectors;
+
 import org.apache.cloudstack.config.ApiServiceConfiguration;
 import org.apache.cloudstack.framework.config.ConfigKey;
 import org.apache.cloudstack.framework.messagebus.MessageBus;
@@ -32,16 +36,17 @@
 import org.junit.Test;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
+import org.mockito.Mockito;
 import org.mockito.MockitoAnnotations;
 import org.mockito.Spy;
 
-import java.lang.reflect.Field;
-import java.util.ArrayList;
-import java.util.Arrays;
-import java.util.HashSet;
-import java.util.List;
-
-import static org.mockito.Mockito.when;
+import com.cloud.agent.AgentManager;
+import com.cloud.host.Host;
+import com.cloud.host.HostVO;
+import com.cloud.host.dao.HostDao;
+import com.cloud.hypervisor.Hypervisor;
+import com.cloud.resource.ResourceState;
+import com.cloud.utils.exception.CloudRuntimeException;
 
 public class IndirectAgentLBServiceImplTest {
 
@@ -85,6 +90,7 @@ private void addField(final IndirectAgentLBServiceImpl provider, final String na
     }
 
     private void configureMocks() throws NoSuchFieldException, IllegalAccessException {
+        List<HostVO> hosts = Arrays.asList(host1, host2, host3, host4);
         long id = 1;
         for (HostVO h : Arrays.asList(host1, host2, host3, host4)) {
             when(h.getId()).thenReturn(id);
@@ -98,7 +104,9 @@ private void configureMocks() throws NoSuchFieldException, IllegalAccessExceptio
         addField(agentMSLB, "hostDao", hostDao);
         addField(agentMSLB, "agentManager", agentManager);
 
-        when(hostDao.listAll()).thenReturn(Arrays.asList(host4, host2, host1, host3));
+        List<Long> hostIds = hosts.stream().map(HostVO::getId).collect(Collectors.toList());
+        doReturn(hostIds).when(hostDao).findHostIdsByZoneClusterResourceStateTypeAndHypervisorType(Mockito.anyLong(),
+                Mockito.eq(null), Mockito.anyList(), Mockito.anyList(), Mockito.anyList());
     }
 
     @Before
@@ -193,21 +201,18 @@ public void testExceptionOnEmptyHostSetting() throws NoSuchFieldException, Illeg
     }
 
     @Test
-    public void testGetOrderedRunningHostIdsNullList() {
-        when(hostDao.listAll()).thenReturn(null);
-        Assert.assertTrue(agentMSLB.getOrderedHostIdList(DC_1_ID).size() == 0);
+    public void testGetOrderedRunningHostIdsEmptyList() {
+        doReturn(Collections.emptyList()).when(hostDao).findHostIdsByZoneClusterResourceStateTypeAndHypervisorType(
+                Mockito.eq(DC_1_ID), Mockito.eq(null), Mockito.anyList(), Mockito.anyList(), Mockito.anyList());
+        Assert.assertTrue(agentMSLB.getOrderedHostIdList(DC_1_ID).isEmpty());
     }
 
     @Test
     public void testGetOrderedRunningHostIdsOrderList() {
-        when(hostDao.listAll()).thenReturn(Arrays.asList(host4, host2, host1, host3));
+        doReturn(Arrays.asList(host4.getId(), host2.getId(), host1.getId(), host3.getId())).when(hostDao)
+                .findHostIdsByZoneClusterResourceStateTypeAndHypervisorType(Mockito.eq(DC_1_ID), Mockito.eq(null),
+                        Mockito.anyList(), Mockito.anyList(), Mockito.anyList());
         Assert.assertEquals(Arrays.asList(host1.getId(), host2.getId(), host3.getId(), host4.getId()),
                 agentMSLB.getOrderedHostIdList(DC_1_ID));
     }
-
-    @Test
-    public void testGetHostsPerZoneNullHosts() {
-        when(hostDao.listAll()).thenReturn(null);
-        Assert.assertTrue(agentMSLB.getOrderedHostIdList(DC_2_ID).size() == 0);
-    }
 }
diff --git a/server/src/test/java/org/apache/cloudstack/networkoffering/CreateNetworkOfferingTest.java b/server/src/test/java/org/apache/cloudstack/networkoffering/CreateNetworkOfferingTest.java
index 25b4bdda45f1..403b14965b14 100644
--- a/server/src/test/java/org/apache/cloudstack/networkoffering/CreateNetworkOfferingTest.java
+++ b/server/src/test/java/org/apache/cloudstack/networkoffering/CreateNetworkOfferingTest.java
@@ -18,7 +18,6 @@
 package org.apache.cloudstack.networkoffering;
 
 import static org.mockito.ArgumentMatchers.any;
-import static org.mockito.ArgumentMatchers.anyString;
 import static org.mockito.ArgumentMatchers.nullable;
 
 import java.util.HashMap;
@@ -28,21 +27,21 @@
 
 import javax.inject.Inject;
 
-import com.cloud.network.dao.PublicIpQuarantineDao;
 import org.apache.cloudstack.annotation.dao.AnnotationDao;
 import org.apache.cloudstack.context.CallContext;
 import org.apache.cloudstack.framework.config.dao.ConfigurationDao;
-import org.apache.cloudstack.framework.config.impl.ConfigurationVO;
 import org.apache.cloudstack.resourcedetail.dao.UserIpAddressDetailsDao;
 import org.junit.After;
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
+import org.mockito.InjectMocks;
+import org.mockito.Mock;
 import org.mockito.Mockito;
-import org.springframework.test.context.ContextConfiguration;
-import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
+import org.mockito.junit.MockitoJUnitRunner;
 
 import com.cloud.configuration.ConfigurationManager;
+import com.cloud.configuration.ConfigurationManagerImpl;
 import com.cloud.dc.dao.VlanDetailsDao;
 import com.cloud.event.dao.UsageEventDao;
 import com.cloud.event.dao.UsageEventDetailsDao;
@@ -52,6 +51,7 @@
 import com.cloud.network.Network.Service;
 import com.cloud.network.Networks.TrafficType;
 import com.cloud.network.dao.LoadBalancerVMMapDao;
+import com.cloud.network.dao.PublicIpQuarantineDao;
 import com.cloud.network.vpc.VpcManager;
 import com.cloud.offering.NetworkOffering.Availability;
 import com.cloud.offerings.NetworkOfferingServiceMapVO;
@@ -61,48 +61,44 @@
 import com.cloud.user.AccountManager;
 import com.cloud.user.AccountVO;
 import com.cloud.user.UserVO;
-import com.cloud.utils.component.ComponentContext;
 import com.cloud.vm.dao.UserVmDetailsDao;
+
 import junit.framework.TestCase;
 
-@RunWith(SpringJUnit4ClassRunner.class)
-@ContextConfiguration(locations = "classpath:/createNetworkOffering.xml")
+@RunWith(MockitoJUnitRunner.class)
 public class CreateNetworkOfferingTest extends TestCase {
 
-    @Inject
-    ConfigurationManager configMgr;
-
-    @Inject
+    @Mock
     ConfigurationDao configDao;
 
-    @Inject
+    @Mock
     NetworkOfferingDao offDao;
 
-    @Inject
+    @Mock
     NetworkOfferingServiceMapDao mapDao;
 
-    @Inject
+    @Mock
     AccountManager accountMgr;
 
-    @Inject
+    @Mock
     VpcManager vpcMgr;
 
-    @Inject
+    @Mock
     UserVmDetailsDao userVmDetailsDao;
 
-    @Inject
+    @Mock
     UsageEventDao UsageEventDao;
 
-    @Inject
+    @Mock
     UsageEventDetailsDao usageEventDetailsDao;
 
-    @Inject
+    @Mock
     UserIpAddressDetailsDao userIpAddressDetailsDao;
 
-    @Inject
+    @Mock
     LoadBalancerVMMapDao _loadBalancerVMMapDao;
 
-    @Inject
+    @Mock
     AnnotationDao annotationDao;
     @Inject
     VlanDetailsDao vlanDetailsDao;
@@ -110,15 +106,12 @@ public class CreateNetworkOfferingTest extends TestCase {
     @Inject
     PublicIpQuarantineDao publicIpQuarantineDao;
 
+    @InjectMocks
+    ConfigurationManager configMgr = new ConfigurationManagerImpl();
+
     @Override
     @Before
     public void setUp() {
-        ComponentContext.initComponentsLifeCycle();
-
-        ConfigurationVO configVO = new ConfigurationVO("200", "200", "200", "200", "200", "200");
-        Mockito.when(configDao.findByName(anyString())).thenReturn(configVO);
-
-        Mockito.when(offDao.persist(any(NetworkOfferingVO.class))).thenReturn(new NetworkOfferingVO());
         Mockito.when(offDao.persist(any(NetworkOfferingVO.class), nullable(Map.class))).thenReturn(new NetworkOfferingVO());
         Mockito.when(mapDao.persist(any(NetworkOfferingServiceMapVO.class))).thenReturn(new NetworkOfferingServiceMapVO());
         Mockito.when(accountMgr.getSystemUser()).thenReturn(new UserVO(1));
diff --git a/services/secondary-storage/controller/src/main/java/org/apache/cloudstack/secondarystorage/SecondaryStorageManagerImpl.java b/services/secondary-storage/controller/src/main/java/org/apache/cloudstack/secondarystorage/SecondaryStorageManagerImpl.java
index ec1e8a81979e..8a6c981e5693 100644
--- a/services/secondary-storage/controller/src/main/java/org/apache/cloudstack/secondarystorage/SecondaryStorageManagerImpl.java
+++ b/services/secondary-storage/controller/src/main/java/org/apache/cloudstack/secondarystorage/SecondaryStorageManagerImpl.java
@@ -16,6 +16,8 @@
 // under the License.
 package org.apache.cloudstack.secondarystorage;
 
+import static com.cloud.configuration.Config.SecStorageAllowedInternalDownloadSites;
+
 import java.net.URI;
 import java.net.URISyntaxException;
 import java.util.ArrayList;
@@ -157,8 +159,6 @@
 import com.cloud.vm.dao.UserVmDetailsDao;
 import com.cloud.vm.dao.VMInstanceDao;
 
-import static com.cloud.configuration.Config.SecStorageAllowedInternalDownloadSites;
-
 /**
 * Class to manage secondary storages. <br><br>
 * Possible secondary storage VM state transition cases:<br>
@@ -810,11 +810,9 @@ public void allocCapacity(long dataCenterId, SecondaryStorageVm.Role role) {
     }
 
     public boolean isZoneReady(Map<Long, ZoneHostInfo> zoneHostInfoMap, long dataCenterId) {
-        List <HostVO> hosts = _hostDao.listByDataCenterId(dataCenterId);
-        if (CollectionUtils.isEmpty(hosts)) {
-            if (logger.isDebugEnabled()) {
-                logger.debug("Zone " + dataCenterId + " has no host available which is enabled and in Up state");
-            }
+        Integer totalUpAndEnabledHosts = _hostDao.countUpAndEnabledHostsInZone(dataCenterId);
+        if (totalUpAndEnabledHosts != null && totalUpAndEnabledHosts < 1) {
+            logger.debug("Zone {} has no host available which is enabled and in Up state", dataCenterId);
             return false;
         }
         ZoneHostInfo zoneHostInfo = zoneHostInfoMap.get(dataCenterId);
@@ -841,8 +839,8 @@ public boolean isZoneReady(Map<Long, ZoneHostInfo> zoneHostInfoMap, long dataCen
             }
 
             boolean useLocalStorage = BooleanUtils.toBoolean(ConfigurationManagerImpl.SystemVMUseLocalStorage.valueIn(dataCenterId));
-            List<Pair<Long, Integer>> storagePoolHostInfos = _storagePoolHostDao.getDatacenterStoragePoolHostInfo(dataCenterId, !useLocalStorage);
-            if (CollectionUtils.isNotEmpty(storagePoolHostInfos) && storagePoolHostInfos.get(0).second() > 0) {
+            boolean hasStoragePoolHostInfo = _storagePoolHostDao.hasDatacenterStoragePoolHostInfo(dataCenterId, !useLocalStorage);
+            if (hasStoragePoolHostInfo) {
                 return true;
             } else {
                 if (logger.isDebugEnabled()) {
diff --git a/setup/db/create-schema-simulator.sql b/setup/db/create-schema-simulator.sql
index 73896af1f12b..f52faa043d8f 100644
--- a/setup/db/create-schema-simulator.sql
+++ b/setup/db/create-schema-simulator.sql
@@ -64,7 +64,8 @@ CREATE TABLE `simulator`.`mockstoragepool` (
   `capacity` bigint,
   `pool_type` varchar(40),
   `hostguid` varchar(255) UNIQUE,
-  PRIMARY KEY  (`id`)
+  PRIMARY KEY  (`id`),
+  INDEX `i_mockstoragepool__guid`(`guid`)
 ) ENGINE=InnoDB DEFAULT CHARSET=utf8;
 
 
diff --git a/test/integration/smoke/test_dynamicroles.py b/test/integration/smoke/test_dynamicroles.py
index b91ba9c2eba8..e404835fbb8a 100644
--- a/test/integration/smoke/test_dynamicroles.py
+++ b/test/integration/smoke/test_dynamicroles.py
@@ -18,7 +18,7 @@
 from marvin.cloudstackAPI import *
 from marvin.cloudstackTestCase import cloudstackTestCase
 from marvin.cloudstackException import CloudstackAPIException
-from marvin.lib.base import Account, Role, RolePermission
+from marvin.lib.base import Account, Role, RolePermission, Configurations
 from marvin.lib.utils import cleanup_resources
 from nose.plugins.attrib import attr
 from random import shuffle
@@ -26,6 +26,7 @@
 import copy
 import random
 import re
+import time
 
 
 class TestData(object):
@@ -109,6 +110,14 @@ def setUp(self):
             self.testdata["account"],
             roleid=self.role.id
         )
+
+        cache_period_config = Configurations.list(
+            self.apiclient,
+            name='dynamic.apichecker.cache.period'
+        )[0]
+
+        self.cache_period = int(cache_period_config.value)
+
         self.cleanup = [
             self.account,
             self.rolepermission,
@@ -623,6 +632,8 @@ def test_role_account_acls(self):
                 testdata
             )
 
+        time.sleep(self.cache_period + 5)
+
         userApiClient = self.getUserApiClient(self.account.name, domain=self.account.domain, role_type=self.account.roletype)
 
         # Perform listApis check
@@ -645,6 +656,8 @@ def test_role_account_acls_multiple_mgmt_servers(self):
             self.dbclient.execute("insert into role_permissions (uuid, role_id, rule, permission, sort_order) values (UUID(), %d, '%s', '%s', %d)" % (roleId, rule, perm.upper(), sortOrder))
             sortOrder += 1
 
+        time.sleep(self.cache_period + 5)
+
         userApiClient = self.getUserApiClient(self.account.name, domain=self.account.domain, role_type=self.account.roletype)
 
         # Perform listApis check
diff --git a/tools/marvin/setup.py b/tools/marvin/setup.py
index 0618d84370a4..679b1d5920d8 100644
--- a/tools/marvin/setup.py
+++ b/tools/marvin/setup.py
@@ -27,7 +27,7 @@
         raise RuntimeError("python setuptools is required to build Marvin")
 
 
-VERSION = "4.20.0.0-SNAPSHOT"
+VERSION = "4.20.0.0"
 
 setup(name="Marvin",
       version=VERSION,
diff --git a/ui/src/config/section/infra/hosts.js b/ui/src/config/section/infra/hosts.js
index 727da7242d7d..5def7f3b7fc1 100644
--- a/ui/src/config/section/infra/hosts.js
+++ b/ui/src/config/section/infra/hosts.js
@@ -27,7 +27,7 @@ export default {
   searchFilters: ['name', 'zoneid', 'podid', 'clusterid', 'hypervisor'],
   resourceType: 'Host',
   filters: () => {
-    const filters = ['enabled', 'disabled', 'maintenance', 'up', 'down', 'alert']
+    const filters = ['enabled', 'disabled', 'maintenance', 'up', 'down', 'disconnected', 'alert']
     return filters
   },
   params: { type: 'routing' },
diff --git a/ui/src/views/AutogenView.vue b/ui/src/views/AutogenView.vue
index bfdde77191ee..0209e1440d4d 100644
--- a/ui/src/views/AutogenView.vue
+++ b/ui/src/views/AutogenView.vue
@@ -1752,7 +1752,7 @@ export default {
         if (filter === 'all') {
           delete query.resourcestate
           delete query.state
-        } else if (['up', 'down', 'alert'].includes(filter)) {
+        } else if (['up', 'down', 'disconnected', 'alert'].includes(filter)) {
           delete query.resourcestate
           query.state = filter
         } else {
diff --git a/ui/src/views/dashboard/CapacityDashboard.vue b/ui/src/views/dashboard/CapacityDashboard.vue
index dae53cf0015b..76a72243ac9d 100644
--- a/ui/src/views/dashboard/CapacityDashboard.vue
+++ b/ui/src/views/dashboard/CapacityDashboard.vue
@@ -41,7 +41,7 @@
         <div class="capacity-dashboard-button">
           <a-button
             shape="round"
-            @click="() => { updateData(zoneSelected); listAlerts(); listEvents(); }">
+            @click="() => { updateData(zoneSelected, true); listAlerts(); listEvents(); }">
             <reload-outlined/>
             {{ $t('label.fetch.latest') }}
           </a-button>
@@ -170,7 +170,7 @@
       </chart-card>
     </a-col>
     <a-col :xs="{ span: 24 }" :lg="{ span: 12 }" :xl="{ span: 8 }" :xxl="{ span: 8 }">
-      <chart-card :loading="loading" class="dashboard-card">
+      <chart-card :loading="capacityLoading" class="dashboard-card">
         <template #title>
           <div class="center">
             <h3><cloud-outlined /> {{ $t('label.compute') }}</h3>
@@ -200,7 +200,7 @@
       </chart-card>
     </a-col>
     <a-col :xs="{ span: 24 }" :lg="{ span: 12 }" :xl="{ span: 8 }" :xxl="{ span: 8 }">
-      <chart-card :loading="loading" class="dashboard-card">
+      <chart-card :loading="capacityLoading" class="dashboard-card">
         <template #title>
           <div class="center">
             <h3><hdd-outlined /> {{ $t('label.storage') }}</h3>
@@ -230,7 +230,7 @@
       </chart-card>
     </a-col>
     <a-col :xs="{ span: 24 }" :lg="{ span: 12 }" :xl="{ span: 8 }" :xxl="{ span: 8 }">
-      <chart-card :loading="loading" class="dashboard-card">
+      <chart-card :loading="capacityLoading" class="dashboard-card">
         <template #title>
           <div class="center">
             <h3><apartment-outlined /> {{ $t('label.network') }}</h3>
@@ -340,6 +340,7 @@ export default {
   data () {
     return {
       loading: true,
+      capacityLoading: true,
       tabKey: 'alerts',
       alerts: [],
       events: [],
@@ -431,9 +432,9 @@ export default {
       this.listEvents()
     },
     listCapacity (zone, latest = false, additive = false) {
-      this.loading = true
+      this.capacityLoading = true
       api('listCapacity', { zoneid: zone.id, fetchlatest: latest }).then(json => {
-        this.loading = false
+        this.capacityLoading = false
         let stats = []
         if (json && json.listcapacityresponse && json.listcapacityresponse.capacity) {
           stats = json.listcapacityresponse.capacity
@@ -457,15 +458,14 @@ export default {
         }
       })
     },
-    updateData (zone) {
+    updateData (zone, latest = false) {
+      this.statsMap = {}
       if (!zone.id) {
-        this.statsMap = {}
         for (const zone of this.zones.slice(1)) {
-          this.listCapacity(zone, true, true)
+          this.listCapacity(zone, latest, true)
         }
       } else {
-        this.statsMap = {}
-        this.listCapacity(this.zoneSelected, true)
+        this.listCapacity(this.zoneSelected, latest)
       }
 
       this.data = {
diff --git a/utils/src/main/java/com/cloud/utils/backoff/impl/ConstantTimeBackoff.java b/utils/src/main/java/com/cloud/utils/backoff/impl/ConstantTimeBackoff.java
index ac21036c59e1..043c77a9a0de 100644
--- a/utils/src/main/java/com/cloud/utils/backoff/impl/ConstantTimeBackoff.java
+++ b/utils/src/main/java/com/cloud/utils/backoff/impl/ConstantTimeBackoff.java
@@ -54,7 +54,6 @@ public void waitBeforeRetry() {
         } finally {
             _asleep.remove(current.getName());
         }
-        return;
     }
 
     @Override
diff --git a/utils/src/main/java/com/cloud/utils/nio/Link.java b/utils/src/main/java/com/cloud/utils/nio/Link.java
index 71d881a94aec..5404cd153439 100644
--- a/utils/src/main/java/com/cloud/utils/nio/Link.java
+++ b/utils/src/main/java/com/cloud/utils/nio/Link.java
@@ -48,8 +48,9 @@
 import org.apache.cloudstack.framework.ca.CAService;
 import org.apache.cloudstack.utils.security.KeyStoreUtils;
 import org.apache.cloudstack.utils.security.SSLUtils;
-import org.apache.logging.log4j.Logger;
+import org.apache.commons.lang3.ObjectUtils;
 import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
 
 import com.cloud.utils.PropertiesUtil;
 import com.cloud.utils.exception.CloudRuntimeException;
@@ -592,6 +593,10 @@ private static HandshakeHolder doHandshakeWrap(final SocketChannel socketChannel
     }
 
     public static boolean doHandshake(final SocketChannel socketChannel, final SSLEngine sslEngine) throws IOException {
+        return doHandshake(socketChannel, sslEngine, null);
+    }
+
+    public static boolean doHandshake(final SocketChannel socketChannel, final SSLEngine sslEngine, Integer timeout) throws IOException {
         if (socketChannel == null || sslEngine == null) {
             return false;
         }
@@ -606,12 +611,15 @@ public static boolean doHandshake(final SocketChannel socketChannel, final SSLEn
         final long startTimeMills = System.currentTimeMillis();
 
         HandshakeStatus handshakeStatus = sslEngine.getHandshakeStatus();
+        long timeoutMillis = ObjectUtils.defaultIfNull(timeout, 30) * 1000L;
         while (handshakeStatus != SSLEngineResult.HandshakeStatus.FINISHED
                 && handshakeStatus != SSLEngineResult.HandshakeStatus.NOT_HANDSHAKING) {
             final long timeTaken = System.currentTimeMillis() - startTimeMills;
-            if (timeTaken > 30000L) {
-                LOGGER.warn("SSL Handshake has taken more than 30s to connect to: " + socketChannel.getRemoteAddress() +
-                        ". Please investigate this connection.");
+
+            if (timeTaken > timeoutMillis) {
+                LOGGER.warn("SSL Handshake has taken more than {}ms to connect to: {}" +
+                        " while status: {}. Please investigate this connection.", socketChannel.getRemoteAddress(),
+                        handshakeStatus);
                 return false;
             }
             switch (handshakeStatus) {
diff --git a/utils/src/main/java/com/cloud/utils/nio/NioClient.java b/utils/src/main/java/com/cloud/utils/nio/NioClient.java
index 89f51399e266..70a88aa0fc81 100644
--- a/utils/src/main/java/com/cloud/utils/nio/NioClient.java
+++ b/utils/src/main/java/com/cloud/utils/nio/NioClient.java
@@ -33,73 +33,84 @@
 
 public class NioClient extends NioConnection {
 
-    protected String _host;
-    protected SocketChannel _clientConnection;
+    protected String host;
+    protected SocketChannel clientConnection;
 
-    public NioClient(final String name, final String host, final int port, final int workers, final HandlerFactory factory) {
-        super(name, port, workers, factory);
-        _host = host;
+    public NioClient(final String name, final String host, final int port, final int workers, final Integer sslHandshakeTimeout, final HandlerFactory factory) {
+        super(name, port, workers, 1, 2, factory);
+        setSslHandshakeTimeout(sslHandshakeTimeout);
+        this.host = host;
+    }
+
+    protected void closeChannel() {
+        try {
+            if (clientConnection != null && clientConnection.isOpen()) {
+                clientConnection.close();
+            }
+        } catch (IOException e) {
+            logger.error("Failed to close SocketChannel", e);
+        }
     }
 
     @Override
     protected void init() throws IOException {
-        _selector = Selector.open();
-        Task task = null;
-
+        Task task;
+        String hostLog = host + ":" + _port;
         try {
-            _clientConnection = SocketChannel.open();
-
-            logger.info("Connecting to " + _host + ":" + _port);
-            final InetSocketAddress peerAddr = new InetSocketAddress(_host, _port);
-            _clientConnection.connect(peerAddr);
-            _clientConnection.configureBlocking(false);
+            logger.info("Connecting to {}", hostLog);
+            _selector = Selector.open();
+            clientConnection = SocketChannel.open();
+            final InetSocketAddress serverAddress = new InetSocketAddress(host, _port);
+            clientConnection.connect(serverAddress);
+            logger.info("Connected to {}", hostLog);
+            clientConnection.configureBlocking(false);
 
             final SSLContext sslContext = Link.initClientSSLContext();
-            SSLEngine sslEngine = sslContext.createSSLEngine(_host, _port);
+            SSLEngine sslEngine = sslContext.createSSLEngine(host, _port);
             sslEngine.setUseClientMode(true);
             sslEngine.setEnabledProtocols(SSLUtils.getSupportedProtocols(sslEngine.getEnabledProtocols()));
             sslEngine.beginHandshake();
-            if (!Link.doHandshake(_clientConnection, sslEngine)) {
-                logger.error("SSL Handshake failed while connecting to host: " + _host + " port: " + _port);
-                _selector.close();
-                throw new IOException("SSL Handshake failed while connecting to host: " + _host + " port: " + _port);
+            if (!Link.doHandshake(clientConnection, sslEngine, getSslHandshakeTimeout())) {
+                throw new IOException(String.format("SSL Handshake failed while connecting to host: %s", hostLog));
             }
             logger.info("SSL: Handshake done");
-            logger.info("Connected to " + _host + ":" + _port);
 
-            final Link link = new Link(peerAddr, this);
+            final Link link = new Link(serverAddress, this);
             link.setSSLEngine(sslEngine);
-            final SelectionKey key = _clientConnection.register(_selector, SelectionKey.OP_READ);
+            final SelectionKey key = clientConnection.register(_selector, SelectionKey.OP_READ);
             link.setKey(key);
             key.attach(link);
             // Notice we've already connected due to the handshake, so let's get the
             // remaining task done
             task = _factory.create(Task.Type.CONNECT, link, null);
         } catch (final GeneralSecurityException e) {
-            _selector.close();
+            closeChannel();
             throw new IOException("Failed to initialise security", e);
         } catch (final IOException e) {
-            _selector.close();
+            closeChannel();
+            logger.error(String.format("IOException while connecting to %s", hostLog), e);
             throw e;
         }
-        _executor.submit(task);
+        if (task != null) {
+            _executor.submit(task);
+        }
     }
 
     @Override
-    protected void registerLink(final InetSocketAddress saddr, final Link link) {
+    protected void registerLink(final InetSocketAddress address, final Link link) {
         // don't do anything.
     }
 
     @Override
-    protected void unregisterLink(final InetSocketAddress saddr) {
+    protected void unregisterLink(final InetSocketAddress address) {
         // don't do anything.
     }
 
     @Override
     public void cleanUp() throws IOException {
         super.cleanUp();
-        if (_clientConnection != null) {
-            _clientConnection.close();
+        if (clientConnection != null && clientConnection.isOpen()) {
+            clientConnection.close();
         }
         logger.info("NioClient connection closed");
     }
diff --git a/utils/src/main/java/com/cloud/utils/nio/NioConnection.java b/utils/src/main/java/com/cloud/utils/nio/NioConnection.java
index 6be42a2ee330..5284058787b8 100644
--- a/utils/src/main/java/com/cloud/utils/nio/NioConnection.java
+++ b/utils/src/main/java/com/cloud/utils/nio/NioConnection.java
@@ -32,24 +32,29 @@
 import java.nio.channels.Selector;
 import java.nio.channels.ServerSocketChannel;
 import java.nio.channels.SocketChannel;
+import java.security.GeneralSecurityException;
 import java.util.ArrayList;
 import java.util.Iterator;
 import java.util.List;
 import java.util.Set;
+import java.util.concurrent.BlockingQueue;
 import java.util.concurrent.Callable;
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
 import java.util.concurrent.Future;
 import java.util.concurrent.LinkedBlockingQueue;
+import java.util.concurrent.RejectedExecutionException;
+import java.util.concurrent.SynchronousQueue;
 import java.util.concurrent.ThreadPoolExecutor;
 import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicInteger;
 
 import javax.net.ssl.SSLEngine;
 
 import org.apache.cloudstack.framework.ca.CAService;
 import org.apache.cloudstack.utils.security.SSLUtils;
-import org.apache.logging.log4j.Logger;
 import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
 
 import com.cloud.utils.concurrency.NamedThreadFactory;
 import com.cloud.utils.exception.NioConnectionException;
@@ -60,6 +65,7 @@
  */
 public abstract class NioConnection implements Callable<Boolean> {
     protected Logger logger = LogManager.getLogger(getClass());
+    public static final String SERVER_BUSY_MESSAGE = "Server is busy.";
 
     protected Selector _selector;
     protected ExecutorService _threadExecutor;
@@ -74,15 +80,27 @@ public abstract class NioConnection implements Callable<Boolean> {
     protected ExecutorService _executor;
     protected ExecutorService _sslHandshakeExecutor;
     protected CAService caService;
-
-    public NioConnection(final String name, final int port, final int workers, final HandlerFactory factory) {
+    protected Integer sslHandshakeTimeout = null;
+    private final int sslHandshakeMaxWorkers;
+    private final AtomicInteger activeAcceptConnections = new AtomicInteger(0);
+    private final BlockingQueue<Runnable> workerQueue;
+    private final BlockingQueue<Runnable> sslHandshakeQueue;
+
+    public NioConnection(final String name, final int port, final int workers, final int sslHandshakeMinWorkers,
+             final int sslHandshakeMaxWorkers, final HandlerFactory factory) {
         _name = name;
         _isRunning = false;
         _selector = null;
         _port = port;
         _factory = factory;
-        _executor = new ThreadPoolExecutor(workers, 5 * workers, 1, TimeUnit.DAYS, new LinkedBlockingQueue<Runnable>(), new NamedThreadFactory(name + "-Handler"));
-        _sslHandshakeExecutor = Executors.newCachedThreadPool(new NamedThreadFactory(name + "-SSLHandshakeHandler"));
+        this.sslHandshakeMaxWorkers = Math.max(sslHandshakeMaxWorkers, 1);
+        workerQueue = new LinkedBlockingQueue<>(5 * workers);
+        _executor = new ThreadPoolExecutor(workers, 5 * workers, 1, TimeUnit.DAYS,
+                workerQueue, new NamedThreadFactory(name + "-Handler"), new ThreadPoolExecutor.AbortPolicy());
+        sslHandshakeQueue = new SynchronousQueue<>();
+        _sslHandshakeExecutor = new ThreadPoolExecutor(Math.max(sslHandshakeMinWorkers, 0), this.sslHandshakeMaxWorkers, 30,
+                TimeUnit.MINUTES, sslHandshakeQueue, new NamedThreadFactory(name + "-SSLHandshakeHandler"),
+                new ThreadPoolExecutor.AbortPolicy());
     }
 
     public void setCAService(final CAService caService) {
@@ -95,8 +113,8 @@ public void start() throws NioConnectionException {
         try {
             init();
         } catch (final ConnectException e) {
-            logger.warn("Unable to connect to remote: is there a server running on port " + _port);
-            return;
+            logger.warn("Unable to connect to remote: is there a server running on port" + _port, e);
+            throw new NioConnectionException(e.getMessage(), e);
         } catch (final IOException e) {
             logger.error("Unable to initialize the threads.", e);
             throw new NioConnectionException(e.getMessage(), e);
@@ -113,6 +131,7 @@ public void start() throws NioConnectionException {
 
     public void stop() {
         _executor.shutdown();
+        _sslHandshakeExecutor.shutdown();
         _isRunning = false;
         if (_threadExecutor != null) {
             _futureTask.cancel(false);
@@ -190,9 +209,25 @@ public Boolean call() throws NioConnectionException {
 
     abstract void unregisterLink(InetSocketAddress saddr);
 
+    protected boolean rejectConnectionIfBusy(final SocketChannel socketChannel) throws IOException {
+        if (activeAcceptConnections.get() < sslHandshakeMaxWorkers) {
+            return false;
+        }
+        // Reject new connection if the server is busy
+        logger.warn(String.format("%s Rejecting new connection. %d active connections currently",
+                SERVER_BUSY_MESSAGE, sslHandshakeMaxWorkers));
+        socketChannel.close();
+        _selector.wakeup();
+        return true;
+    }
+
+
     protected void accept(final SelectionKey key) throws IOException {
         final ServerSocketChannel serverSocketChannel = (ServerSocketChannel)key.channel();
         final SocketChannel socketChannel = serverSocketChannel.accept();
+        if (rejectConnectionIfBusy(socketChannel)) {
+            return;
+        }
         socketChannel.configureBlocking(false);
 
         final Socket socket = socketChannel.socket();
@@ -202,57 +237,64 @@ protected void accept(final SelectionKey key) throws IOException {
             logger.trace("Connection accepted for " + socket);
         }
 
-        final SSLEngine sslEngine;
         try {
-            sslEngine = Link.initServerSSLEngine(caService, socketChannel.getRemoteAddress().toString());
-            sslEngine.setUseClientMode(false);
-            sslEngine.setEnabledProtocols(SSLUtils.getSupportedProtocols(sslEngine.getEnabledProtocols()));
             final NioConnection nioConnection = this;
-            _sslHandshakeExecutor.submit(new Runnable() {
-                @Override
-                public void run() {
-                    _selector.wakeup();
-                    try {
-                        sslEngine.beginHandshake();
-                        if (!Link.doHandshake(socketChannel, sslEngine)) {
-                            throw new IOException("SSL handshake timed out with " + socketChannel.getRemoteAddress());
-                        }
-                        if (logger.isTraceEnabled()) {
-                            logger.trace("SSL: Handshake done");
-                        }
-                        final InetSocketAddress saddr = (InetSocketAddress)socket.getRemoteSocketAddress();
-                        final Link link = new Link(saddr, nioConnection);
-                        link.setSSLEngine(sslEngine);
-                        link.setKey(socketChannel.register(key.selector(), SelectionKey.OP_READ, link));
-                        final Task task = _factory.create(Task.Type.CONNECT, link, null);
-                        registerLink(saddr, link);
-                        _executor.submit(task);
-                    } catch (IOException e) {
-                        if (logger.isTraceEnabled()) {
-                            logger.trace("Connection closed due to failure: " + e.getMessage());
-                        }
-                        closeAutoCloseable(socket, "accepting socket");
-                        closeAutoCloseable(socketChannel, "accepting socketChannel");
-                    } finally {
-                        _selector.wakeup();
+            _sslHandshakeExecutor.submit(() -> {
+                final InetSocketAddress socketAddress = (InetSocketAddress)socket.getRemoteSocketAddress();
+                activeAcceptConnections.incrementAndGet();
+                long startTime = System.currentTimeMillis();
+                _selector.wakeup();
+                try {
+                    final SSLEngine sslEngine = Link.initServerSSLEngine(caService, socketChannel.getRemoteAddress().toString());
+                    sslEngine.setUseClientMode(false);
+                    sslEngine.setEnabledProtocols(SSLUtils.getSupportedProtocols(sslEngine.getEnabledProtocols()));
+                    sslEngine.beginHandshake();
+                    if (!Link.doHandshake(socketChannel, sslEngine, getSslHandshakeTimeout())) {
+                        throw new IOException("SSL handshake timed out with " + socketAddress);
+                    }
+                    if (logger.isTraceEnabled()) {
+                        logger.trace("SSL: Handshake done");
                     }
+                    final Link link = new Link(socketAddress, nioConnection);
+                    link.setSSLEngine(sslEngine);
+                    link.setKey(socketChannel.register(key.selector(), SelectionKey.OP_READ, link));
+                    final Task task = _factory.create(Task.Type.CONNECT, link, null);
+                    registerLink(socketAddress, link);
+                    _executor.submit(task);
+                } catch (final GeneralSecurityException | IOException e) {
+                    if (logger.isTraceEnabled()) {
+                        logger.trace(socket.getRemoteSocketAddress()+ "Connection closed due to failure: " + e.getMessage());
+                    }
+                    closeAutoCloseable(socket, "accepting socket");
+                    closeAutoCloseable(socketChannel, "accepting socketChannel");
+                } finally {
+                    int connections = activeAcceptConnections.decrementAndGet();
+                    if (logger.isTraceEnabled()) {
+                        logger.trace(String.format("Accept task complete for %s - time taken: %d, " +
+                                        "active accept connections: %d",
+                                socketAddress, (System.currentTimeMillis() - startTime), connections));
+                    }
+                    _selector.wakeup();
                 }
             });
-        } catch (final Exception e) {
+        } catch (final RejectedExecutionException e) {
             if (logger.isTraceEnabled()) {
-                logger.trace("Connection closed due to failure: " + e.getMessage());
+                logger.trace("{} Accept Task rejected: {}", socket.getRemoteSocketAddress(), e.getMessage());
             }
-            closeAutoCloseable(socket, "accepting socket");
-            closeAutoCloseable(socketChannel, "accepting socketChannel");
+            closeAutoCloseable(socket, "Rejecting connection - accepting socket");
+            closeAutoCloseable(socketChannel, "Rejecting connection - accepting socketChannel");
         } finally {
             _selector.wakeup();
         }
     }
 
-    protected void terminate(final SelectionKey key) {
+    protected void terminate(final SelectionKey key, String msg) {
         final Link link = (Link)key.attachment();
         closeConnection(key);
         if (link != null) {
+            if (logger.isTraceEnabled()) {
+                logger.warn("Will terminate connection due to: " + msg);
+            }
             link.terminated();
             final Task task = _factory.create(Task.Type.DISCONNECT, link, null);
             unregisterLink(link.getSocketAddress());
@@ -288,7 +330,7 @@ protected void read(final SelectionKey key) throws IOException {
             }
         } catch (final Exception e) {
             logDebug(e, key, 1);
-            terminate(key);
+            terminate(key, e.getMessage());
         }
     }
 
@@ -413,11 +455,11 @@ protected void connect(final SelectionKey key) throws IOException {
             try {
                 _executor.submit(task);
             } catch (final Exception e) {
-                logger.warn("Exception occurred when submitting the task", e);
+                logger.warn("Exception occurred when submitting the task for connect: {}", socket, e);
             }
         } catch (final IOException e) {
             logTrace(e, key, 2);
-            terminate(key);
+            terminate(key, e.getMessage());
         }
     }
 
@@ -444,7 +486,7 @@ protected void write(final SelectionKey key) throws IOException {
             }
         } catch (final Exception e) {
             logDebug(e, key, 3);
-            terminate(key);
+            terminate(key, e.getMessage());
         }
     }
 
@@ -491,7 +533,8 @@ public void close(final SelectionKey key) {
 
     /* Release the resource used by the instance */
     public void cleanUp() throws IOException {
-        if (_selector != null) {
+        if (_selector != null && _selector.isOpen()) {
+            _selector.wakeup();
             _selector.close();
         }
     }
@@ -513,4 +556,12 @@ public ChangeRequest(final Object key, final int type, final int ops, final Obje
             this.att = att;
         }
     }
+
+    public Integer getSslHandshakeTimeout() {
+        return sslHandshakeTimeout;
+    }
+
+    public void setSslHandshakeTimeout(Integer sslHandshakeTimeout) {
+        this.sslHandshakeTimeout = sslHandshakeTimeout;
+    }
 }
diff --git a/utils/src/main/java/com/cloud/utils/nio/NioServer.java b/utils/src/main/java/com/cloud/utils/nio/NioServer.java
index dfc42b5fd211..b384da225481 100644
--- a/utils/src/main/java/com/cloud/utils/nio/NioServer.java
+++ b/utils/src/main/java/com/cloud/utils/nio/NioServer.java
@@ -31,54 +31,57 @@
 
 public class NioServer extends NioConnection {
 
-    protected InetSocketAddress _localAddr;
-    private ServerSocketChannel _serverSocket;
+    protected InetSocketAddress localAddress;
+    private ServerSocketChannel serverSocket;
 
-    protected WeakHashMap<InetSocketAddress, Link> _links;
+    protected WeakHashMap<InetSocketAddress, Link> links;
 
-    public NioServer(final String name, final int port, final int workers, final HandlerFactory factory, final CAService caService) {
-        super(name, port, workers, factory);
+    public NioServer(final String name, final int port, final int workers, final int sslHandshakeMinWorkers,
+             final int sslHandshakeMaxWorkers, final HandlerFactory factory, final CAService caService,
+             final Integer sslHandShakeTimeout) {
+        super(name, port, workers, sslHandshakeMinWorkers, sslHandshakeMaxWorkers, factory);
         setCAService(caService);
-        _localAddr = null;
-        _links = new WeakHashMap<InetSocketAddress, Link>(1024);
+        setSslHandshakeTimeout(sslHandShakeTimeout);
+        localAddress = null;
+        links = new WeakHashMap<>(1024);
     }
 
     public int getPort() {
-        return _serverSocket.socket().getLocalPort();
+        return serverSocket.socket().getLocalPort();
     }
 
     @Override
     protected void init() throws IOException {
         _selector = SelectorProvider.provider().openSelector();
 
-        _serverSocket = ServerSocketChannel.open();
-        _serverSocket.configureBlocking(false);
+        serverSocket = ServerSocketChannel.open();
+        serverSocket.configureBlocking(false);
 
-        _localAddr = new InetSocketAddress(_port);
-        _serverSocket.socket().bind(_localAddr);
+        localAddress = new InetSocketAddress(_port);
+        serverSocket.socket().bind(localAddress);
 
-        _serverSocket.register(_selector, SelectionKey.OP_ACCEPT, null);
+        serverSocket.register(_selector, SelectionKey.OP_ACCEPT, null);
 
-        logger.info("NioServer started and listening on " + _serverSocket.socket().getLocalSocketAddress());
+        logger.info("NioServer started and listening on {}", serverSocket.socket().getLocalSocketAddress());
     }
 
     @Override
     public void cleanUp() throws IOException {
         super.cleanUp();
-        if (_serverSocket != null) {
-            _serverSocket.close();
+        if (serverSocket != null && serverSocket.isOpen()) {
+            serverSocket.close();
         }
-        logger.info("NioConnection stopped on " + _localAddr.toString());
+        logger.info("NioConnection stopped on {}",  localAddress.toString());
     }
 
     @Override
     protected void registerLink(final InetSocketAddress addr, final Link link) {
-        _links.put(addr, link);
+        links.put(addr, link);
     }
 
     @Override
     protected void unregisterLink(final InetSocketAddress saddr) {
-        _links.remove(saddr);
+        links.remove(saddr);
     }
 
     /**
@@ -91,7 +94,7 @@ protected void unregisterLink(final InetSocketAddress saddr) {
      * @return null if not sent.  attach object in link if sent.
      */
     public Object send(final InetSocketAddress saddr, final byte[] data) throws ClosedChannelException {
-        final Link link = _links.get(saddr);
+        final Link link = links.get(saddr);
         if (link == null) {
             return null;
         }
diff --git a/utils/src/main/java/org/apache/cloudstack/utils/cache/LazyCache.java b/utils/src/main/java/org/apache/cloudstack/utils/cache/LazyCache.java
new file mode 100644
index 000000000000..0b4c91e24b3c
--- /dev/null
+++ b/utils/src/main/java/org/apache/cloudstack/utils/cache/LazyCache.java
@@ -0,0 +1,48 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+package org.apache.cloudstack.utils.cache;
+
+import java.util.concurrent.TimeUnit;
+import java.util.function.Function;
+
+import com.github.benmanes.caffeine.cache.Caffeine;
+import com.github.benmanes.caffeine.cache.LoadingCache;
+
+public class LazyCache<K, V> {
+
+    private final LoadingCache<K, V> cache;
+
+    public LazyCache(long maximumSize, long expireAfterWriteSeconds, Function<K, V> loader) {
+        this.cache = Caffeine.newBuilder()
+                .maximumSize(maximumSize)
+                .expireAfterWrite(expireAfterWriteSeconds, TimeUnit.SECONDS)
+                .build(loader::apply);
+    }
+
+    public V get(K key) {
+        return cache.get(key);
+    }
+
+    public void invalidate(K key) {
+        cache.invalidate(key);
+    }
+
+    public void clear() {
+        cache.invalidateAll();
+    }
+}
diff --git a/utils/src/main/java/org/apache/cloudstack/utils/cache/SingleCache.java b/utils/src/main/java/org/apache/cloudstack/utils/cache/SingleCache.java
new file mode 100644
index 000000000000..5fa77d9a28c9
--- /dev/null
+++ b/utils/src/main/java/org/apache/cloudstack/utils/cache/SingleCache.java
@@ -0,0 +1,48 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+package org.apache.cloudstack.utils.cache;
+
+import java.util.concurrent.TimeUnit;
+import java.util.function.Supplier;
+
+import com.github.benmanes.caffeine.cache.Caffeine;
+import com.github.benmanes.caffeine.cache.LoadingCache;
+
+public class SingleCache<V> {
+
+    private final LoadingCache<Integer, V> cache;
+
+    public SingleCache(long expireAfterWriteSeconds, Supplier<V> loader) {
+        this.cache = Caffeine.newBuilder()
+                .maximumSize(1)
+                .expireAfterWrite(expireAfterWriteSeconds, TimeUnit.SECONDS)
+                .build(key -> loader.get());
+    }
+
+    public V get() {
+        return cache.get(0);
+    }
+
+    public void invalidate() {
+        cache.invalidate(0);
+    }
+
+    public void clear() {
+        cache.invalidateAll();
+    }
+}
diff --git a/utils/src/test/java/com/cloud/utils/testcase/NioTest.java b/utils/src/test/java/com/cloud/utils/testcase/NioTest.java
index a08814876f98..46339e568af8 100644
--- a/utils/src/test/java/com/cloud/utils/testcase/NioTest.java
+++ b/utils/src/test/java/com/cloud/utils/testcase/NioTest.java
@@ -19,21 +19,6 @@
 
 package com.cloud.utils.testcase;
 
-import com.cloud.utils.concurrency.NamedThreadFactory;
-import com.cloud.utils.exception.NioConnectionException;
-import com.cloud.utils.nio.HandlerFactory;
-import com.cloud.utils.nio.Link;
-import com.cloud.utils.nio.NioClient;
-import com.cloud.utils.nio.NioServer;
-import com.cloud.utils.nio.Task;
-import com.cloud.utils.nio.Task.Type;
-import org.apache.logging.log4j.Logger;
-import org.apache.logging.log4j.LogManager;
-import org.junit.After;
-import org.junit.Assert;
-import org.junit.Before;
-import org.junit.Test;
-
 import java.io.IOException;
 import java.net.InetSocketAddress;
 import java.nio.channels.ClosedChannelException;
@@ -45,6 +30,22 @@
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
 
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+import org.junit.After;
+import org.junit.Assert;
+import org.junit.Before;
+import org.junit.Test;
+
+import com.cloud.utils.concurrency.NamedThreadFactory;
+import com.cloud.utils.exception.NioConnectionException;
+import com.cloud.utils.nio.HandlerFactory;
+import com.cloud.utils.nio.Link;
+import com.cloud.utils.nio.NioClient;
+import com.cloud.utils.nio.NioServer;
+import com.cloud.utils.nio.Task;
+import com.cloud.utils.nio.Task.Type;
+
 /**
  * NioTest demonstrates that NioServer can function without getting its main IO
  * loop blocked when an aggressive or malicious client connects to the server but
@@ -99,7 +100,7 @@ public void setUp() {
         testBytes = new byte[1000000];
         randomGenerator.nextBytes(testBytes);
 
-        server = new NioServer("NioTestServer", 0, 1, new NioTestServer(), null);
+        server = new NioServer("NioTestServer", 0, 1, 1, 2 * totalTestCount, new NioTestServer(), null,  null);
         try {
             server.start();
         } catch (final NioConnectionException e) {
@@ -111,7 +112,7 @@ public void setUp() {
             maliciousClients.add(maliciousClient);
             maliciousExecutor.submit(new ThreadedNioClient(maliciousClient));
 
-            final NioClient client = new NioClient("NioTestClient-" + i, "127.0.0.1", server.getPort(), 1, new NioTestClient());
+            final NioClient client = new NioClient("NioTestClient-" + i, "127.0.0.1", server.getPort(), 1, null, new NioTestClient());
             clients.add(client);
             clientExecutor.submit(new ThreadedNioClient(client));
         }
@@ -180,17 +181,17 @@ public void run() {
     public class NioMaliciousClient extends NioClient {
 
         public NioMaliciousClient(String name, String host, int port, int workers, HandlerFactory factory) {
-            super(name, host, port, workers, factory);
+            super(name, host, port, workers, null, factory);
         }
 
         @Override
         protected void init() throws IOException {
             _selector = Selector.open();
             try {
-                _clientConnection = SocketChannel.open();
-                logger.info("Connecting to " + _host + ":" + _port);
-                final InetSocketAddress peerAddr = new InetSocketAddress(_host, _port);
-                _clientConnection.connect(peerAddr);
+                clientConnection = SocketChannel.open();
+                logger.info("Connecting to {}:{}", host, _port);
+                final InetSocketAddress peerAddr = new InetSocketAddress(host, _port);
+                clientConnection.connect(peerAddr);
                 // This is done on purpose, the malicious client would connect
                 // to the server and then do nothing, hence using a large sleep value
                 Thread.sleep(Long.MAX_VALUE);
diff --git a/utils/src/test/java/org/apache/cloudstack/utils/cache/LazyCacheTest.java b/utils/src/test/java/org/apache/cloudstack/utils/cache/LazyCacheTest.java
new file mode 100644
index 000000000000..75d31b95fcc3
--- /dev/null
+++ b/utils/src/test/java/org/apache/cloudstack/utils/cache/LazyCacheTest.java
@@ -0,0 +1,115 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+package org.apache.cloudstack.utils.cache;
+
+import static org.junit.Assert.assertEquals;
+
+import java.util.function.Function;
+
+import org.junit.Assert;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.Mockito;
+import org.mockito.junit.MockitoJUnitRunner;
+
+@RunWith(MockitoJUnitRunner.class)
+public class LazyCacheTest {
+    private final long expireSeconds = 1;
+    private final String cacheValuePrefix = "ComputedValueFor:";
+    private LazyCache<String, String> cache;
+    private Function<String, String> mockLoader;
+
+    @Before
+    public void setUp() {
+        mockLoader = Mockito.mock(Function.class);
+        Mockito.when(mockLoader.apply(Mockito.anyString())).thenAnswer(invocation -> cacheValuePrefix + invocation.getArgument(0));
+        cache = new LazyCache<>(4, expireSeconds, mockLoader);
+    }
+
+    @Test
+    public void testCacheMissAndLoader() {
+        String key = "key1";
+        String value = cache.get(key);
+        assertEquals(cacheValuePrefix + key, value);
+        Mockito.verify(mockLoader).apply(key);
+    }
+
+    @Test
+    public void testLoaderNotCalledIfPresent() {
+        String key = "key2";
+        cache.get(key);
+        try {
+            Thread.sleep((long)(0.9 * expireSeconds * 1000));
+        } catch (InterruptedException ie) {
+            Assert.fail(String.format("Exception occurred: %s", ie.getMessage()));
+        }
+        cache.get(key);
+        Mockito.verify(mockLoader, Mockito.times(1)).apply(key);
+    }
+
+    @Test
+    public void testCacheExpiration() {
+        String key = "key3";
+        cache.get(key);
+        try {
+            Thread.sleep((long)(1.1 * expireSeconds * 1000));
+        } catch (InterruptedException ie) {
+            Assert.fail(String.format("Exception occurred: %s", ie.getMessage()));
+        }
+        cache.get(key);
+        Mockito.verify(mockLoader, Mockito.times(2)).apply(key);
+    }
+
+    @Test
+    public void testInvalidateKey() {
+        String key = "key4";
+        cache.get(key);
+        cache.invalidate(key);
+        cache.get(key);
+        Mockito.verify(mockLoader, Mockito.times(2)).apply(key);
+    }
+
+    @Test
+    public void testClearCache() {
+        String key1 = "key5";
+        String key2 = "key6";
+        cache.get(key1);
+        cache.get(key2);
+        cache.clear();
+        cache.get(key1);
+        Mockito.verify(mockLoader, Mockito.times(2)).apply(key1);
+        Mockito.verify(mockLoader, Mockito.times(1)).apply(key2);
+    }
+
+    @Test
+    public void testMaximumSize() {
+        String key = "key7";
+        cache.get(key);
+        for (int i = 0; i < 4; i++) {
+            cache.get(String.format("newkey-%d", i));
+        }
+        try {
+            Thread.sleep(100);
+        } catch (InterruptedException ie) {
+            Assert.fail(String.format("Exception occurred: %s", ie.getMessage()));
+        }
+        cache.get(key);
+        Mockito.verify(mockLoader, Mockito.times(2)).apply(key);
+    }
+}