diff --git a/yarn/alpha/src/main/scala/org/apache/spark/deploy/yarn/ApplicationMaster.scala b/yarn/alpha/src/main/scala/org/apache/spark/deploy/yarn/ApplicationMaster.scala
index 46a01f5a9a2cc..f79ddf84a6d71 100644
--- a/yarn/alpha/src/main/scala/org/apache/spark/deploy/yarn/ApplicationMaster.scala
+++ b/yarn/alpha/src/main/scala/org/apache/spark/deploy/yarn/ApplicationMaster.scala
@@ -18,7 +18,6 @@
 package org.apache.spark.deploy.yarn
 
 import java.io.IOException
-import java.net.Socket
 import java.util.concurrent.CopyOnWriteArrayList
 import java.util.concurrent.atomic.{AtomicInteger, AtomicReference}
 
@@ -58,12 +57,12 @@ class ApplicationMaster(args: ApplicationMasterArguments, conf: Configuration,
   private val fs = FileSystem.get(yarnConf)
 
   private var yarnAllocator: YarnAllocationHandler = _
-  private var isFinished: Boolean = false
+  @volatile private var isFinished: Boolean = false
   private var uiAddress: String = _
   private var uiHistoryAddress: String = _
   private val maxAppAttempts: Int = conf.getInt(YarnConfiguration.RM_AM_MAX_RETRIES,
     YarnConfiguration.DEFAULT_RM_AM_MAX_RETRIES)
-  private var isLastAMRetry: Boolean = true
+  @volatile private var isLastAMRetry: Boolean = true
 
   // Default to numExecutors * 2, with minimum of 3
   private val maxNumExecutorFailures = sparkConf.getInt("spark.yarn.max.executor.failures",
diff --git a/yarn/alpha/src/main/scala/org/apache/spark/deploy/yarn/ExecutorLauncher.scala b/yarn/alpha/src/main/scala/org/apache/spark/deploy/yarn/ExecutorLauncher.scala
index 72c7143edcd71..2021797cf8bb3 100644
--- a/yarn/alpha/src/main/scala/org/apache/spark/deploy/yarn/ExecutorLauncher.scala
+++ b/yarn/alpha/src/main/scala/org/apache/spark/deploy/yarn/ExecutorLauncher.scala
@@ -58,7 +58,7 @@ class ExecutorLauncher(args: ApplicationMasterArguments, conf: Configuration, sp
   private var yarnAllocator: YarnAllocationHandler = _
 
   private var driverClosed: Boolean = false
-  private var isFinished: Boolean = false
+  @volatile private var isFinished: Boolean = false
   private var registered: Boolean = false
 
   // Default to numExecutors * 2, with minimum of 3
diff --git a/yarn/stable/src/main/scala/org/apache/spark/deploy/yarn/ApplicationMaster.scala b/yarn/stable/src/main/scala/org/apache/spark/deploy/yarn/ApplicationMaster.scala
index 9c2bcf17a8508..62bd10a25cd55 100644
--- a/yarn/stable/src/main/scala/org/apache/spark/deploy/yarn/ApplicationMaster.scala
+++ b/yarn/stable/src/main/scala/org/apache/spark/deploy/yarn/ApplicationMaster.scala
@@ -57,12 +57,12 @@ class ApplicationMaster(args: ApplicationMasterArguments, conf: Configuration,
   private val fs = FileSystem.get(yarnConf)
 
   private var yarnAllocator: YarnAllocationHandler = _
-  private var isFinished: Boolean = false
+  @volatile private var isFinished: Boolean = false
   private var uiAddress: String = _
   private var uiHistoryAddress: String = _
   private val maxAppAttempts: Int = conf.getInt(
     YarnConfiguration.RM_AM_MAX_ATTEMPTS, YarnConfiguration.DEFAULT_RM_AM_MAX_ATTEMPTS)
-  private var isLastAMRetry: Boolean = true
+  @volatile private var isLastAMRetry: Boolean = true
   private var amClient: AMRMClient[ContainerRequest] = _
 
   // Default to numExecutors * 2, with minimum of 3
diff --git a/yarn/stable/src/main/scala/org/apache/spark/deploy/yarn/ExecutorLauncher.scala b/yarn/stable/src/main/scala/org/apache/spark/deploy/yarn/ExecutorLauncher.scala
index a7585748b7f88..a6e66dd438c41 100644
--- a/yarn/stable/src/main/scala/org/apache/spark/deploy/yarn/ExecutorLauncher.scala
+++ b/yarn/stable/src/main/scala/org/apache/spark/deploy/yarn/ExecutorLauncher.scala
@@ -55,7 +55,7 @@ class ExecutorLauncher(args: ApplicationMasterArguments, conf: Configuration, sp
 
   private var yarnAllocator: YarnAllocationHandler = _
   private var driverClosed: Boolean = false
-  private var isFinished: Boolean = false
+  @volatile private var isFinished: Boolean = false
   private var registered: Boolean = false
 
   private var amClient: AMRMClient[ContainerRequest] = _