[SPARK-19450] Replace askWithRetry with askSync.

jinxing · Yun Ni · commit 486607abd608 · 2017-02-27T15:54:11.000-08:00
## What changes were proposed in this pull request? `askSync` is already added in `RpcEndpointRef` (see SPARK-19347 and apache#16690 (comment)) and `askWithRetry` is marked as deprecated. As mentioned SPARK-18113(apache#16503 (comment)): >askWithRetry is basically an unneeded API, and a leftover from the akka days that doesn't make sense anymore. It's prone to cause deadlocks (exactly because it's blocking), it imposes restrictions on the caller (e.g. idempotency) and other things that people generally don't pay that much attention to when using it. Since `askWithRetry` is just used inside spark and not in user logic. It might make sense to replace all of them with `askSync`. ## How was this patch tested? This PR doesn't change code logic, existing unit test can cover. Author: jinxing <jinxing@meituan.com> Closes apache#16790 from jinxing64/SPARK-19450.
diff --git a/core/src/main/scala/org/apache/spark/MapOutputTracker.scala b/core/src/main/scala/org/apache/spark/MapOutputTracker.scala
@@ -99,7 +99,7 @@ private[spark] abstract class MapOutputTracker(conf: SparkConf) extends Logging
    */
   protected def askTracker[T: ClassTag](message: Any): T = {
     try {
-      trackerEndpoint.askWithRetry[T](message)
+      trackerEndpoint.askSync[T](message)
     } catch {
       case e: Exception =>
         logError("Error communicating with MapOutputTracker", e)
diff --git a/core/src/main/scala/org/apache/spark/SparkContext.scala b/core/src/main/scala/org/apache/spark/SparkContext.scala
@@ -605,7 +605,7 @@ class SparkContext(config: SparkConf) extends Logging {
         Some(Utils.getThreadDump())
       } else {
         val endpointRef = env.blockManager.master.getExecutorEndpointRef(executorId).get
-        Some(endpointRef.askWithRetry[Array[ThreadStackTrace]](TriggerThreadDump))
+        Some(endpointRef.askSync[Array[ThreadStackTrace]](TriggerThreadDump))
       }
     } catch {
       case e: Exception =>
diff --git a/core/src/main/scala/org/apache/spark/deploy/Client.scala b/core/src/main/scala/org/apache/spark/deploy/Client.scala
@@ -123,7 +123,7 @@ private class ClientEndpoint(
     Thread.sleep(5000)
     logInfo("... polling master for driver state")
     val statusResponse =
-      activeMasterEndpoint.askWithRetry[DriverStatusResponse](RequestDriverStatus(driverId))
+      activeMasterEndpoint.askSync[DriverStatusResponse](RequestDriverStatus(driverId))
     if (statusResponse.found) {
       logInfo(s"State of $driverId is ${statusResponse.state.get}")
       // Worker node, if present
diff --git a/core/src/main/scala/org/apache/spark/deploy/master/Master.scala b/core/src/main/scala/org/apache/spark/deploy/master/Master.scala
@@ -1045,7 +1045,7 @@ private[deploy] object Master extends Logging {
     val rpcEnv = RpcEnv.create(SYSTEM_NAME, host, port, conf, securityMgr)
     val masterEndpoint = rpcEnv.setupEndpoint(ENDPOINT_NAME,
       new Master(rpcEnv, rpcEnv.address, webUiPort, securityMgr, conf))
-    val portsResponse = masterEndpoint.askWithRetry[BoundPortsResponse](BoundPortsRequest)
+    val portsResponse = masterEndpoint.askSync[BoundPortsResponse](BoundPortsRequest)
     (rpcEnv, portsResponse.webUIPort, portsResponse.restPort)
   }
 }
diff --git a/core/src/main/scala/org/apache/spark/deploy/master/ui/ApplicationPage.scala b/core/src/main/scala/org/apache/spark/deploy/master/ui/ApplicationPage.scala
@@ -34,7 +34,7 @@ private[ui] class ApplicationPage(parent: MasterWebUI) extends WebUIPage("app")
   /** Executor details for a particular application */
   def render(request: HttpServletRequest): Seq[Node] = {
     val appId = request.getParameter("appId")
-    val state = master.askWithRetry[MasterStateResponse](RequestMasterState)
+    val state = master.askSync[MasterStateResponse](RequestMasterState)
     val app = state.activeApps.find(_.id == appId)
       .getOrElse(state.completedApps.find(_.id == appId).orNull)
     if (app == null) {
diff --git a/core/src/main/scala/org/apache/spark/deploy/master/ui/MasterPage.scala b/core/src/main/scala/org/apache/spark/deploy/master/ui/MasterPage.scala
@@ -33,7 +33,7 @@ private[ui] class MasterPage(parent: MasterWebUI) extends WebUIPage("") {
   private val master = parent.masterEndpointRef
 
   def getMasterState: MasterStateResponse = {
-    master.askWithRetry[MasterStateResponse](RequestMasterState)
+    master.askSync[MasterStateResponse](RequestMasterState)
   }
 
   override def renderJson(request: HttpServletRequest): JValue = {
diff --git a/core/src/main/scala/org/apache/spark/deploy/rest/StandaloneRestServer.scala b/core/src/main/scala/org/apache/spark/deploy/rest/StandaloneRestServer.scala
@@ -71,7 +71,7 @@ private[rest] class StandaloneKillRequestServlet(masterEndpoint: RpcEndpointRef,
   extends KillRequestServlet {
 
   protected def handleKill(submissionId: String): KillSubmissionResponse = {
-    val response = masterEndpoint.askWithRetry[DeployMessages.KillDriverResponse](
+    val response = masterEndpoint.askSync[DeployMessages.KillDriverResponse](
       DeployMessages.RequestKillDriver(submissionId))
     val k = new KillSubmissionResponse
     k.serverSparkVersion = sparkVersion
@@ -89,7 +89,7 @@ private[rest] class StandaloneStatusRequestServlet(masterEndpoint: RpcEndpointRe
   extends StatusRequestServlet {
 
   protected def handleStatus(submissionId: String): SubmissionStatusResponse = {
-    val response = masterEndpoint.askWithRetry[DeployMessages.DriverStatusResponse](
+    val response = masterEndpoint.askSync[DeployMessages.DriverStatusResponse](
       DeployMessages.RequestDriverStatus(submissionId))
     val message = response.exception.map { s"Exception from the cluster:\n" + formatException(_) }
     val d = new SubmissionStatusResponse
@@ -174,7 +174,7 @@ private[rest] class StandaloneSubmitRequestServlet(
     requestMessage match {
       case submitRequest: CreateSubmissionRequest =>
         val driverDescription = buildDriverDescription(submitRequest)
-        val response = masterEndpoint.askWithRetry[DeployMessages.SubmitDriverResponse](
+        val response = masterEndpoint.askSync[DeployMessages.SubmitDriverResponse](
           DeployMessages.RequestSubmitDriver(driverDescription))
         val submitResponse = new CreateSubmissionResponse
         submitResponse.serverSparkVersion = sparkVersion
diff --git a/core/src/main/scala/org/apache/spark/deploy/worker/ui/WorkerPage.scala b/core/src/main/scala/org/apache/spark/deploy/worker/ui/WorkerPage.scala
@@ -34,12 +34,12 @@ private[ui] class WorkerPage(parent: WorkerWebUI) extends WebUIPage("") {
   private val workerEndpoint = parent.worker.self
 
   override def renderJson(request: HttpServletRequest): JValue = {
-    val workerState = workerEndpoint.askWithRetry[WorkerStateResponse](RequestWorkerState)
+    val workerState = workerEndpoint.askSync[WorkerStateResponse](RequestWorkerState)
     JsonProtocol.writeWorkerState(workerState)
   }
 
   def render(request: HttpServletRequest): Seq[Node] = {
-    val workerState = workerEndpoint.askWithRetry[WorkerStateResponse](RequestWorkerState)
+    val workerState = workerEndpoint.askSync[WorkerStateResponse](RequestWorkerState)
 
     val executorHeaders = Seq("ExecutorID", "Cores", "State", "Memory", "Job Details", "Logs")
     val runningExecutors = workerState.executors
diff --git a/core/src/main/scala/org/apache/spark/executor/CoarseGrainedExecutorBackend.scala b/core/src/main/scala/org/apache/spark/executor/CoarseGrainedExecutorBackend.scala
@@ -199,7 +199,7 @@ private[spark] object CoarseGrainedExecutorBackend extends Logging {
         new SecurityManager(executorConf),
         clientMode = true)
       val driver = fetcher.setupEndpointRefByURI(driverUrl)
-      val cfg = driver.askWithRetry[SparkAppConfig](RetrieveSparkAppConfig)
+      val cfg = driver.askSync[SparkAppConfig](RetrieveSparkAppConfig)
       val props = cfg.sparkProperties ++ Seq[(String, String)](("spark.app.id", appId))
       fetcher.shutdown()
 
diff --git a/core/src/main/scala/org/apache/spark/executor/Executor.scala b/core/src/main/scala/org/apache/spark/executor/Executor.scala
@@ -677,7 +677,7 @@ private[spark] class Executor(
 
     val message = Heartbeat(executorId, accumUpdates.toArray, env.blockManager.blockManagerId)
     try {
-      val response = heartbeatReceiverRef.askWithRetry[HeartbeatResponse](
+      val response = heartbeatReceiverRef.askSync[HeartbeatResponse](
           message, RpcTimeout(conf, "spark.executor.heartbeatInterval", "10s"))
       if (response.reregisterBlockManager) {
         logInfo("Told to re-register on heartbeat")
diff --git a/core/src/main/scala/org/apache/spark/rpc/RpcEndpointRef.scala b/core/src/main/scala/org/apache/spark/rpc/RpcEndpointRef.scala
@@ -92,64 +92,4 @@ private[spark] abstract class RpcEndpointRef(conf: SparkConf)
     timeout.awaitResult(future)
   }
 
-  /**
-   * Send a message to the corresponding [[RpcEndpoint.receiveAndReply]] and get its result within a
-   * default timeout, throw a SparkException if this fails even after the default number of retries.
-   * The default `timeout` will be used in every trial of calling `sendWithReply`. Because this
-   * method retries, the message handling in the receiver side should be idempotent.
-   *
-   * Note: this is a blocking action which may cost a lot of time,  so don't call it in a message
-   * loop of [[RpcEndpoint]].
-   *
-   * @param message the message to send
-   * @tparam T type of the reply message
-   * @return the reply message from the corresponding [[RpcEndpoint]]
-   */
-  @deprecated("use 'askSync' instead.", "2.2.0")
-  def askWithRetry[T: ClassTag](message: Any): T = askWithRetry(message, defaultAskTimeout)
-
-  /**
-   * Send a message to the corresponding [[RpcEndpoint.receiveAndReply]] and get its result within a
-   * specified timeout, throw a SparkException if this fails even after the specified number of
-   * retries. `timeout` will be used in every trial of calling `sendWithReply`. Because this method
-   * retries, the message handling in the receiver side should be idempotent.
-   *
-   * Note: this is a blocking action which may cost a lot of time, so don't call it in a message
-   * loop of [[RpcEndpoint]].
-   *
-   * @param message the message to send
-   * @param timeout the timeout duration
-   * @tparam T type of the reply message
-   * @return the reply message from the corresponding [[RpcEndpoint]]
-   */
-  @deprecated("use 'askSync' instead.", "2.2.0")
-  def askWithRetry[T: ClassTag](message: Any, timeout: RpcTimeout): T = {
-    // TODO: Consider removing multiple attempts
-    var attempts = 0
-    var lastException: Exception = null
-    while (attempts < maxRetries) {
-      attempts += 1
-      try {
-        val future = ask[T](message, timeout)
-        val result = timeout.awaitResult(future)
-        if (result == null) {
-          throw new SparkException("RpcEndpoint returned null")
-        }
-        return result
-      } catch {
-        case ie: InterruptedException => throw ie
-        case e: Exception =>
-          lastException = e
-          logWarning(s"Error sending message [message = $message] in $attempts attempts", e)
-      }
-
-      if (attempts < maxRetries) {
-        Thread.sleep(retryWaitMs)
-      }
-    }
-
-    throw new SparkException(
-      s"Error sending message [message = $message]", lastException)
-  }
-
 }
diff --git a/core/src/main/scala/org/apache/spark/scheduler/DAGScheduler.scala b/core/src/main/scala/org/apache/spark/scheduler/DAGScheduler.scala
@@ -232,7 +232,7 @@ class DAGScheduler(
       accumUpdates: Array[(Long, Int, Int, Seq[AccumulableInfo])],
       blockManagerId: BlockManagerId): Boolean = {
     listenerBus.post(SparkListenerExecutorMetricsUpdate(execId, accumUpdates))
-    blockManagerMaster.driverEndpoint.askWithRetry[Boolean](
+    blockManagerMaster.driverEndpoint.askSync[Boolean](
       BlockManagerHeartbeat(blockManagerId), new RpcTimeout(600 seconds, "BlockManagerHeartbeat"))
   }
 
diff --git a/core/src/main/scala/org/apache/spark/scheduler/cluster/CoarseGrainedSchedulerBackend.scala b/core/src/main/scala/org/apache/spark/scheduler/cluster/CoarseGrainedSchedulerBackend.scala
@@ -372,7 +372,7 @@ class CoarseGrainedSchedulerBackend(scheduler: TaskSchedulerImpl, val rpcEnv: Rp
     try {
       if (driverEndpoint != null) {
         logInfo("Shutting down all executors")
-        driverEndpoint.askWithRetry[Boolean](StopExecutors)
+        driverEndpoint.askSync[Boolean](StopExecutors)
       }
     } catch {
       case e: Exception =>
@@ -384,7 +384,7 @@ class CoarseGrainedSchedulerBackend(scheduler: TaskSchedulerImpl, val rpcEnv: Rp
     stopExecutors()
     try {
       if (driverEndpoint != null) {
-        driverEndpoint.askWithRetry[Boolean](StopDriver)
+        driverEndpoint.askSync[Boolean](StopDriver)
       }
     } catch {
       case e: Exception =>
diff --git a/core/src/main/scala/org/apache/spark/storage/BlockManagerMaster.scala b/core/src/main/scala/org/apache/spark/storage/BlockManagerMaster.scala
@@ -60,7 +60,7 @@ class BlockManagerMaster(
       maxMemSize: Long,
       slaveEndpoint: RpcEndpointRef): BlockManagerId = {
     logInfo(s"Registering BlockManager $blockManagerId")
-    val updatedId = driverEndpoint.askWithRetry[BlockManagerId](
+    val updatedId = driverEndpoint.askSync[BlockManagerId](
       RegisterBlockManager(blockManagerId, maxMemSize, slaveEndpoint))
     logInfo(s"Registered BlockManager $updatedId")
     updatedId
@@ -72,20 +72,20 @@ class BlockManagerMaster(
       storageLevel: StorageLevel,
       memSize: Long,
       diskSize: Long): Boolean = {
-    val res = driverEndpoint.askWithRetry[Boolean](
+    val res = driverEndpoint.askSync[Boolean](
       UpdateBlockInfo(blockManagerId, blockId, storageLevel, memSize, diskSize))
     logDebug(s"Updated info of block $blockId")
     res
   }
 
   /** Get locations of the blockId from the driver */
   def getLocations(blockId: BlockId): Seq[BlockManagerId] = {
-    driverEndpoint.askWithRetry[Seq[BlockManagerId]](GetLocations(blockId))
+    driverEndpoint.askSync[Seq[BlockManagerId]](GetLocations(blockId))
   }
 
   /** Get locations of multiple blockIds from the driver */
   def getLocations(blockIds: Array[BlockId]): IndexedSeq[Seq[BlockManagerId]] = {
-    driverEndpoint.askWithRetry[IndexedSeq[Seq[BlockManagerId]]](
+    driverEndpoint.askSync[IndexedSeq[Seq[BlockManagerId]]](
       GetLocationsMultipleBlockIds(blockIds))
   }
 
@@ -99,24 +99,24 @@ class BlockManagerMaster(
 
   /** Get ids of other nodes in the cluster from the driver */
   def getPeers(blockManagerId: BlockManagerId): Seq[BlockManagerId] = {
-    driverEndpoint.askWithRetry[Seq[BlockManagerId]](GetPeers(blockManagerId))
+    driverEndpoint.askSync[Seq[BlockManagerId]](GetPeers(blockManagerId))
   }
 
   def getExecutorEndpointRef(executorId: String): Option[RpcEndpointRef] = {
-    driverEndpoint.askWithRetry[Option[RpcEndpointRef]](GetExecutorEndpointRef(executorId))
+    driverEndpoint.askSync[Option[RpcEndpointRef]](GetExecutorEndpointRef(executorId))
   }
 
   /**
    * Remove a block from the slaves that have it. This can only be used to remove
    * blocks that the driver knows about.
    */
   def removeBlock(blockId: BlockId) {
-    driverEndpoint.askWithRetry[Boolean](RemoveBlock(blockId))
+    driverEndpoint.askSync[Boolean](RemoveBlock(blockId))
   }
 
   /** Remove all blocks belonging to the given RDD. */
   def removeRdd(rddId: Int, blocking: Boolean) {
-    val future = driverEndpoint.askWithRetry[Future[Seq[Int]]](RemoveRdd(rddId))
+    val future = driverEndpoint.askSync[Future[Seq[Int]]](RemoveRdd(rddId))
     future.onFailure {
       case e: Exception =>
         logWarning(s"Failed to remove RDD $rddId - ${e.getMessage}", e)
@@ -128,7 +128,7 @@ class BlockManagerMaster(
 
   /** Remove all blocks belonging to the given shuffle. */
   def removeShuffle(shuffleId: Int, blocking: Boolean) {
-    val future = driverEndpoint.askWithRetry[Future[Seq[Boolean]]](RemoveShuffle(shuffleId))
+    val future = driverEndpoint.askSync[Future[Seq[Boolean]]](RemoveShuffle(shuffleId))
     future.onFailure {
       case e: Exception =>
         logWarning(s"Failed to remove shuffle $shuffleId - ${e.getMessage}", e)
@@ -140,7 +140,7 @@ class BlockManagerMaster(
 
   /** Remove all blocks belonging to the given broadcast. */
   def removeBroadcast(broadcastId: Long, removeFromMaster: Boolean, blocking: Boolean) {
-    val future = driverEndpoint.askWithRetry[Future[Seq[Int]]](
+    val future = driverEndpoint.askSync[Future[Seq[Int]]](
       RemoveBroadcast(broadcastId, removeFromMaster))
     future.onFailure {
       case e: Exception =>
@@ -159,11 +159,11 @@ class BlockManagerMaster(
    * amount of remaining memory.
    */
   def getMemoryStatus: Map[BlockManagerId, (Long, Long)] = {
-    driverEndpoint.askWithRetry[Map[BlockManagerId, (Long, Long)]](GetMemoryStatus)
+    driverEndpoint.askSync[Map[BlockManagerId, (Long, Long)]](GetMemoryStatus)
   }
 
   def getStorageStatus: Array[StorageStatus] = {
-    driverEndpoint.askWithRetry[Array[StorageStatus]](GetStorageStatus)
+    driverEndpoint.askSync[Array[StorageStatus]](GetStorageStatus)
   }
 
   /**
@@ -184,7 +184,7 @@ class BlockManagerMaster(
      * master endpoint for a response to a prior message.
      */
     val response = driverEndpoint.
-      askWithRetry[Map[BlockManagerId, Future[Option[BlockStatus]]]](msg)
+      askSync[Map[BlockManagerId, Future[Option[BlockStatus]]]](msg)
     val (blockManagerIds, futures) = response.unzip
     implicit val sameThread = ThreadUtils.sameThread
     val cbf =
@@ -214,7 +214,7 @@ class BlockManagerMaster(
       filter: BlockId => Boolean,
       askSlaves: Boolean): Seq[BlockId] = {
     val msg = GetMatchingBlockIds(filter, askSlaves)
-    val future = driverEndpoint.askWithRetry[Future[Seq[BlockId]]](msg)
+    val future = driverEndpoint.askSync[Future[Seq[BlockId]]](msg)
     timeout.awaitResult(future)
   }
 
@@ -223,7 +223,7 @@ class BlockManagerMaster(
    * since they are not reported the master.
    */
   def hasCachedBlocks(executorId: String): Boolean = {
-    driverEndpoint.askWithRetry[Boolean](HasCachedBlocks(executorId))
+    driverEndpoint.askSync[Boolean](HasCachedBlocks(executorId))
   }
 
   /** Stop the driver endpoint, called only on the Spark driver node */
@@ -237,7 +237,7 @@ class BlockManagerMaster(
 
   /** Send a one-way message to the master endpoint, to which we expect it to reply with true. */
   private def tell(message: Any) {
-    if (!driverEndpoint.askWithRetry[Boolean](message)) {
+    if (!driverEndpoint.askSync[Boolean](message)) {
       throw new SparkException("BlockManagerMasterEndpoint returned false, expected true.")
     }
   }
diff --git a/core/src/test/scala/org/apache/spark/deploy/StandaloneDynamicAllocationSuite.scala b/core/src/test/scala/org/apache/spark/deploy/StandaloneDynamicAllocationSuite.scala
@@ -547,7 +547,7 @@ class StandaloneDynamicAllocationSuite
 
   /** Get the Master state */
   private def getMasterState: MasterStateResponse = {
-    master.self.askWithRetry[MasterStateResponse](RequestMasterState)
+    master.self.askSync[MasterStateResponse](RequestMasterState)
   }
 
   /** Get the applications that are active from Master */
@@ -620,7 +620,7 @@ class StandaloneDynamicAllocationSuite
       when(endpointRef.address).thenReturn(mockAddress)
       val message = RegisterExecutor(id, endpointRef, "localhost", 10, Map.empty)
       val backend = sc.schedulerBackend.asInstanceOf[CoarseGrainedSchedulerBackend]
-      backend.driverEndpoint.askWithRetry[Boolean](message)
+      backend.driverEndpoint.askSync[Boolean](message)
     }
   }
 
diff --git a/core/src/test/scala/org/apache/spark/deploy/client/AppClientSuite.scala b/core/src/test/scala/org/apache/spark/deploy/client/AppClientSuite.scala
@@ -171,7 +171,7 @@ class AppClientSuite
 
   /** Get the Master state */
   private def getMasterState: MasterStateResponse = {
-    master.self.askWithRetry[MasterStateResponse](RequestMasterState)
+    master.self.askSync[MasterStateResponse](RequestMasterState)
   }
 
   /** Get the applications that are active from Master */
diff --git a/core/src/test/scala/org/apache/spark/deploy/master/MasterSuite.scala b/core/src/test/scala/org/apache/spark/deploy/master/MasterSuite.scala
@@ -432,7 +432,7 @@ class MasterSuite extends SparkFunSuite
     val master = makeMaster()
     master.rpcEnv.setupEndpoint(Master.ENDPOINT_NAME, master)
     eventually(timeout(10.seconds)) {
-      val masterState = master.self.askWithRetry[MasterStateResponse](RequestMasterState)
+      val masterState = master.self.askSync[MasterStateResponse](RequestMasterState)
       assert(masterState.status === RecoveryState.ALIVE, "Master is not alive")
     }
 
diff --git a/core/src/test/scala/org/apache/spark/rpc/RpcEnvSuite.scala b/core/src/test/scala/org/apache/spark/rpc/RpcEnvSuite.scala
diff --git a/core/src/test/scala/org/apache/spark/storage/BlockManagerSuite.scala b/core/src/test/scala/org/apache/spark/storage/BlockManagerSuite.scala
diff --git a/resource-managers/mesos/src/test/scala/org/apache/spark/scheduler/cluster/mesos/MesosCoarseGrainedSchedulerBackendSuite.scala b/resource-managers/mesos/src/test/scala/org/apache/spark/scheduler/cluster/mesos/MesosCoarseGrainedSchedulerBackendSuite.scala
diff --git a/resource-managers/yarn/src/main/scala/org/apache/spark/deploy/yarn/YarnAllocator.scala b/resource-managers/yarn/src/main/scala/org/apache/spark/deploy/yarn/YarnAllocator.scala
diff --git a/sql/core/src/main/scala/org/apache/spark/sql/execution/streaming/state/StateStoreCoordinator.scala b/sql/core/src/main/scala/org/apache/spark/sql/execution/streaming/state/StateStoreCoordinator.scala
diff --git a/streaming/src/main/scala/org/apache/spark/streaming/receiver/ReceiverSupervisorImpl.scala b/streaming/src/main/scala/org/apache/spark/streaming/receiver/ReceiverSupervisorImpl.scala
diff --git a/streaming/src/main/scala/org/apache/spark/streaming/scheduler/ReceiverTracker.scala b/streaming/src/main/scala/org/apache/spark/streaming/scheduler/ReceiverTracker.scala

Original file line number	Diff line number	Diff line change
`@@ -605,7 +605,7 @@ class SparkContext(config: SparkConf) extends Logging {`
`605`	`605`	`Some(Utils.getThreadDump())`
`606`	`606`	`} else {`
`607`	`607`	`val endpointRef = env.blockManager.master.getExecutorEndpointRef(executorId).get`
`608`		`- Some(endpointRef.askWithRetry[Array[ThreadStackTrace]](TriggerThreadDump))`
	`608`	`+ Some(endpointRef.askSync[Array[ThreadStackTrace]](TriggerThreadDump))`
`609`	`609`	`}`
`610`	`610`	`} catch {`
`611`	`611`	`case e: Exception =>`
Original file line number	Diff line number	Diff line change
`@@ -1045,7 +1045,7 @@ private[deploy] object Master extends Logging {`
`1045`	`1045`	`val rpcEnv = RpcEnv.create(SYSTEM_NAME, host, port, conf, securityMgr)`
`1046`	`1046`	`val masterEndpoint = rpcEnv.setupEndpoint(ENDPOINT_NAME,`
`1047`	`1047`	`new Master(rpcEnv, rpcEnv.address, webUiPort, securityMgr, conf))`
`1048`		`- val portsResponse = masterEndpoint.askWithRetry[BoundPortsResponse](BoundPortsRequest)`
	`1048`	`+ val portsResponse = masterEndpoint.askSync[BoundPortsResponse](BoundPortsRequest)`
`1049`	`1049`	`(rpcEnv, portsResponse.webUIPort, portsResponse.restPort)`
`1050`	`1050`	`}`
`1051`	`1051`	`}`
Original file line number	Diff line number	Diff line change
`@@ -33,7 +33,7 @@ private[ui] class MasterPage(parent: MasterWebUI) extends WebUIPage("") {`
`33`	`33`	`private val master = parent.masterEndpointRef`
`34`	`34`
`35`	`35`	`def getMasterState: MasterStateResponse = {`
`36`		`- master.askWithRetry[MasterStateResponse](RequestMasterState)`
	`36`	`+ master.askSync[MasterStateResponse](RequestMasterState)`
`37`	`37`	`}`
`38`	`38`
`39`	`39`	`override def renderJson(request: HttpServletRequest): JValue = {`