[SPARK-21321][Spark Core] Spark very verbose on shutdown

core/src/main/scala/org/apache/spark/rpc/netty/Dispatcher.scala

@@ -109,8 +109,11 @@ private[netty] class Dispatcher(nettyEnv: NettyRpcEnv) extends Logging {
     val iter = endpoints.keySet().iterator()
     while (iter.hasNext) {
       val name = iter.next
-      postMessage(name, message, (e) => logWarning(s"Message $message dropped. ${e.getMessage}"))
-    }
+        postMessage(name, message, (e) => { e match {
+          case e: RpcEnvStoppedException => logDebug (s"Message $message dropped. ${e.getMessage}")
+          case e: Throwable => logWarning(s"Message $message dropped. ${e.getMessage}")
+        }}
+      )}
   }
 
   /** Posts a message sent by a remote endpoint. */

core/src/main/scala/org/apache/spark/rpc/netty/Inbox.scala

@@ -205,7 +205,12 @@ private[netty] class Inbox(
     try action catch {
       case NonFatal(e) =>
         try endpoint.onError(e) catch {
-          case NonFatal(ee) => logError(s"Ignoring error", ee)
+          case NonFatal(ee) =>
+            if (stopped) {
+              logDebug("Ignoring error", ee)
+            } else {
+              logError("Ignoring error", ee)
+            }
         }
     }
   }

core/src/main/scala/org/apache/spark/rpc/netty/NettyRpcEnv.scala

@@ -185,7 +185,7 @@ private[netty] class NettyRpcEnv(
       try {
         dispatcher.postOneWayMessage(message)
       } catch {
-        case e: RpcEnvStoppedException => logWarning(e.getMessage)
+        case e: RpcEnvStoppedException => logDebug(e.getMessage)
       }
     } else {
       // Message to a remote RPC endpoint.
@@ -203,7 +203,10 @@ private[netty] class NettyRpcEnv(
 
     def onFailure(e: Throwable): Unit = {
       if (!promise.tryFailure(e)) {
-        logWarning(s"Ignored failure: $e")
+        e match {
+          case e : RpcEnvStoppedException => logDebug (s"Ignored failure: $e")
+          case _ => logWarning(s"Ignored failure: $e")
+        }
       }
     }
 

core/src/main/scala/org/apache/spark/rpc/netty/Outbox.scala

@@ -45,7 +45,7 @@ private[netty] case class OneWayOutboxMessage(content: ByteBuffer) extends Outbo
 
   override def onFailure(e: Throwable): Unit = {
     e match {
-      case e1: RpcEnvStoppedException => logWarning(e1.getMessage)
+      case e1: RpcEnvStoppedException => logDebug(e1.getMessage)
       case e1: Throwable => logWarning(s"Failed to send one-way RPC.", e1)
     }
   }

core/src/main/scala/org/apache/spark/scheduler/LiveListenerBus.scala

@@ -136,7 +136,7 @@ private[spark] class LiveListenerBus(conf: SparkConf) extends SparkListenerBus {
   def post(event: SparkListenerEvent): Unit = {
     if (stopped.get) {
       // Drop further events to make `listenerThread` exit ASAP
-      logError(s"$name has already stopped! Dropping event $event")
+      logDebug(s"$name has already stopped! Dropping event $event")
       return
     }
     metrics.numEventsPosted.inc()

resource-managers/yarn/src/main/scala/org/apache/spark/scheduler/cluster/YarnSchedulerBackend.scala

@@ -17,6 +17,8 @@
 
 package org.apache.spark.scheduler.cluster
 
+import java.util.concurrent.atomic.{AtomicBoolean}
+
 import scala.concurrent.{ExecutionContext, Future}
 import scala.util.{Failure, Success}
 import scala.util.control.NonFatal
@@ -40,6 +42,8 @@ private[spark] abstract class YarnSchedulerBackend(
     sc: SparkContext)
   extends CoarseGrainedSchedulerBackend(scheduler, sc.env.rpcEnv) {
 
+  private val stopped = new AtomicBoolean(false)
+
   override val minRegisteredRatio =
     if (conf.getOption("spark.scheduler.minRegisteredResourcesRatio").isEmpty) {
       0.8
@@ -93,6 +97,7 @@ private[spark] abstract class YarnSchedulerBackend(
       requestTotalExecutors(0, 0, Map.empty)
       super.stop()
     } finally {
+      stopped.set(true)
       services.stop()
     }
   }
@@ -206,8 +211,10 @@ private[spark] abstract class YarnSchedulerBackend(
      */
     override def onDisconnected(rpcAddress: RpcAddress): Unit = {
       addressToExecutorId.get(rpcAddress).foreach { executorId =>
-        if (disableExecutor(executorId)) {
-          yarnSchedulerEndpoint.handleExecutorDisconnectedFromDriver(executorId, rpcAddress)
+        if (!stopped.get) {
+          if (disableExecutor(executorId)) {
+            yarnSchedulerEndpoint.handleExecutorDisconnectedFromDriver(executorId, rpcAddress)
+          }
         }
       }
     }