Merge branch 'deprecate-index-thread-pool' into remove-index-thread-pool

* deprecate-index-thread-pool:
  Deprecate the index thread pool

Author: jasontedor

server/src/main/java/org/elasticsearch/threadpool/FixedExecutorBuilder.java

@@ -41,16 +41,28 @@ public final class FixedExecutorBuilder extends ExecutorBuilder<FixedExecutorBui
     private final Setting<Integer> queueSizeSetting;
 
     /**
-     * Construct a fixed executor builder; the settings will have the
-     * key prefix "thread_pool." followed by the executor name.
+     * Construct a fixed executor builder; the settings will have the key prefix "thread_pool." followed by the executor name.
      *
      * @param settings  the node-level settings
      * @param name      the name of the executor
      * @param size      the fixed number of threads
      * @param queueSize the size of the backing queue, -1 for unbounded
      */
     FixedExecutorBuilder(final Settings settings, final String name, final int size, final int queueSize) {
-        this(settings, name, size, queueSize, "thread_pool." + name);
+        this(settings, name, size, queueSize, false);
+    }
+
+    /**
+     * Construct a fixed executor builder; the settings will have the key prefix "thread_pool." followed by the executor name.
+     *
+     * @param settings   the node-level settings
+     * @param name       the name of the executor
+     * @param size       the fixed number of threads
+     * @param queueSize  the size of the backing queue, -1 for unbounded
+     * @param deprecated whether or not the thread pool is deprecated
+     */
+    FixedExecutorBuilder(final Settings settings, final String name, final int size, final int queueSize, final boolean deprecated) {
+        this(settings, name, size, queueSize, "thread_pool." + name, deprecated);
     }
 
     /**
@@ -63,17 +75,41 @@ public final class FixedExecutorBuilder extends ExecutorBuilder<FixedExecutorBui
      * @param prefix    the prefix for the settings keys
      */
     public FixedExecutorBuilder(final Settings settings, final String name, final int size, final int queueSize, final String prefix) {
+        this(settings, name, size, queueSize, prefix, false);
+    }
+
+    /**
+     * Construct a fixed executor builder.
+     *
+     * @param settings  the node-level settings
+     * @param name      the name of the executor
+     * @param size      the fixed number of threads
+     * @param queueSize the size of the backing queue, -1 for unbounded
+     * @param prefix    the prefix for the settings keys
+     */
+    private FixedExecutorBuilder(
+            final Settings settings,
+            final String name,
+            final int size,
+            final int queueSize,
+            final String prefix,
+            final boolean deprecated) {
         super(name);
         final String sizeKey = settingsKey(prefix, "size");
+        final Setting.Property[] properties;
+        if (deprecated) {
+            properties = new Setting.Property[]{Setting.Property.NodeScope, Setting.Property.Deprecated};
+        } else {
+            properties = new Setting.Property[]{Setting.Property.NodeScope};
+        }
         this.sizeSetting =
-            new Setting<>(
-                sizeKey,
-                s -> Integer.toString(size),
-                s -> Setting.parseInt(s, 1, applyHardSizeLimit(settings, name), sizeKey),
-                Setting.Property.NodeScope);
+                new Setting<>(
+                        sizeKey,
+                        s -> Integer.toString(size),
+                        s -> Setting.parseInt(s, 1, applyHardSizeLimit(settings, name), sizeKey),
+                        properties);
         final String queueSizeKey = settingsKey(prefix, "queue_size");
-        this.queueSizeSetting =
-            Setting.intSetting(queueSizeKey, queueSize, Setting.Property.NodeScope);
+        this.queueSizeSetting = Setting.intSetting(queueSizeKey, queueSize, properties);
     }
 
     @Override

server/src/main/java/org/elasticsearch/threadpool/ThreadPool.java

@@ -170,7 +170,7 @@ public ThreadPool(final Settings settings, final ExecutorBuilder<?>... customBui
         final int halfProcMaxAt10 = halfNumberOfProcessorsMaxTen(availableProcessors);
         final int genericThreadPoolMax = boundedBy(4 * availableProcessors, 128, 512);
         builders.put(Names.GENERIC, new ScalingExecutorBuilder(Names.GENERIC, 4, genericThreadPoolMax, TimeValue.timeValueSeconds(30)));
-        builders.put(Names.INDEX, new FixedExecutorBuilder(settings, Names.INDEX, availableProcessors, 200));
+        builders.put(Names.INDEX, new FixedExecutorBuilder(settings, Names.INDEX, availableProcessors, 200, true));
         builders.put(Names.BULK, new FixedExecutorBuilder(settings, Names.BULK, availableProcessors, 200)); // now that we reuse bulk for index/delete ops
         builders.put(Names.GET, new FixedExecutorBuilder(settings, Names.GET, availableProcessors, 1000));
         builders.put(Names.SEARCH, new AutoQueueAdjustingExecutorBuilder(settings,