Throwing exception if SparkHadoopWriter commit denied

However, the Executor will not treat this like any other
ExceptionFailure, but rather send a specific TaskEndReason to the
driver. The driver simply ignores the task that failed to commit after
logging. If the task that attempted to commit first fails, it will be
resubmitted.

TODO unit tests, the current unit tests don't capture this workflow all
the way down to the Executor level.

Author: mccheah

core/src/main/scala/org/apache/spark/CommitDeniedException.scala

@@ -0,0 +1,31 @@
+/*
+ * 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.spark
+
+import org.apache.spark.annotation.DeveloperApi
+
+/**
+ * :: DeveloperApi ::
+ * Exception thrown when a task attempts to commit output to Hadoop, but
+ * is denied by the driver.
+ */
+@DeveloperApi
+class CommitDeniedException(msg: String, jobID: Int, splitID: Int, attemptID: Int)
+  extends Exception(msg) {
+  def toTaskEndReason(): TaskEndReason = new TaskCommitDenied(jobID, splitID, attemptID)
+}

core/src/main/scala/org/apache/spark/SparkHadoopWriter.scala

@@ -122,10 +122,14 @@ class SparkHadoopWriter(@transient jobConf: JobConf)
           }
         }
       } else {
-        logInfo(s"$taID: Not committed because DAGScheduler did not authorize commit")
+        val msg: String = s"$taID: Not committed because the driver did not authorize commit"
+        logInfo(msg)
+        throw new CommitDeniedException(msg, jobID, splitID, attemptID)
       }
     } else {
-      logInfo(s"No need to commit output of task because needsTaskCommit=false: ${taID.value}")
+      val msg: String = s"No need to commit output of task because needsTaskCommit=false: ${taID.value}"
+      logInfo(msg)
+      throw new CommitDeniedException(msg, jobID, splitID, attemptID)
     }
   }
 

core/src/main/scala/org/apache/spark/TaskEndReason.scala

@@ -146,6 +146,20 @@ case object TaskKilled extends TaskFailedReason {
   override def toErrorString: String = "TaskKilled (killed intentionally)"
 }
 
+/**
+ * :: DeveloperApi ::
+ * Task requested the driver to commit, but was denied.
+ */
+@DeveloperApi
+case class TaskCommitDenied(
+    jobID: Int,
+    splitID: Int,
+    attemptID: Int)
+  extends TaskFailedReason {
+  override def toErrorString: String = s"TaskCommitDenied (Driver denied task commit)" +
+    s" for job: $jobID, split: $splitID, attempt: $attemptID"
+}
+
 /**
  * :: DeveloperApi ::
  * The task failed because the executor that it was running on was lost. This may happen because

core/src/main/scala/org/apache/spark/executor/Executor.scala

@@ -248,6 +248,11 @@ private[spark] class Executor(
           execBackend.statusUpdate(taskId, TaskState.KILLED, ser.serialize(TaskKilled))
         }
 
+        case cDE: CommitDeniedException => {
+          val reason = cDE.toTaskEndReason
+          execBackend.statusUpdate(taskId, TaskState.FAILED, ser.serialize(reason))
+        }
+
         case t: Throwable => {
           // Attempt to exit cleanly by informing the driver of our failure.
           // If anything goes wrong (or this was a fatal exception), we will delegate to

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

@@ -1082,6 +1082,9 @@ class DAGScheduler(
           handleExecutorLost(bmAddress.executorId, fetchFailed = true, Some(task.epoch))
         }
 
+      case TaskCommitDenied(jobID, splitID, attemptID) =>
+      // Do nothing here, left up to the TaskScheduler to decide how to handle denied commits
+
       case ExceptionFailure(className, description, stackTrace, fullStackTrace, metrics) =>
         // Do nothing here, left up to the TaskScheduler to decide how to handle user failures
 

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

@@ -17,16 +17,15 @@
 
 package org.apache.spark.scheduler
 
-import java.util.concurrent.{ExecutorService, TimeUnit, Executors, ConcurrentHashMap}
+import java.util.concurrent.{ExecutorService, TimeUnit, ConcurrentHashMap}
 
 import scala.collection.{Map => ScalaImmutableMap}
-import scala.collection.concurrent.{Map => ScalaConcurrentMap}
 import scala.collection.convert.decorateAsScala._
 
 import akka.actor.{ActorRef, Actor}
 
 import org.apache.spark.{SparkConf, Logging}
-import org.apache.spark.util.{AkkaUtils, ActorLogReceive}
+import org.apache.spark.util.{Utils, AkkaUtils, ActorLogReceive}
 
 private[spark] sealed trait OutputCommitCoordinationMessage
 
@@ -119,7 +118,7 @@ private[spark] class OutputCommitCoordinator(conf: SparkConf) extends Logging {
     coordinatorActor = Some(actor)
     executorRequestHandlingThreadPool = {
       if (isDriver) {
-        Some(Executors.newFixedThreadPool(4))
+        Some(Utils.newDaemonFixedThreadPool(8, "OutputCommitCoordinator"))
       } else {
         None
       }
@@ -174,8 +173,15 @@ private[spark] class OutputCommitCoordinator(conf: SparkConf) extends Logging {
       task: TaskId,
       partId: PartitionId,
       attempt: TaskAttemptId): Unit = {
-    executorRequestHandlingThreadPool.foreach(_.submit(
-      new AskCommitRunnable(requester, this, stage, task, partId, attempt)))
+    executorRequestHandlingThreadPool match {
+      case Some(threadPool) =>
+        threadPool.submit(new AskCommitRunnable(requester, this, stage, task, partId, attempt))
+      case None =>
+        logWarning("Got a request to commit output, but the OutputCommitCoordinator was already" +
+          " shut down. Request is being denied.")
+        requester ! false
+    }
+
   }
 
   private def handleTaskCompletion(

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

@@ -646,6 +646,9 @@ private[spark] class TaskSetManager(
             s"${ef.className} (${ef.description}) [duplicate $dupCount]")
         }
 
+      case e: TaskCommitDenied =>
+        logWarning(failureReason)
+
       case e: TaskFailedReason =>  // TaskResultLost, TaskKilled, and others
         logWarning(failureReason)
 
@@ -657,7 +660,7 @@ private[spark] class TaskSetManager(
       put(info.executorId, clock.getTime())
     sched.dagScheduler.taskEnded(tasks(index), reason, null, null, info, taskMetrics)
     addPendingTask(index)
-    if (!isZombie && state != TaskState.KILLED) {
+    if (!isZombie && state != TaskState.KILLED && !reason.isInstanceOf[TaskCommitDenied]) {
       assert (null != failureReason)
       numFailures(index) += 1
       if (numFailures(index) >= maxTaskFailures) {

core/src/test/scala/org/apache/spark/scheduler/DAGSchedulerSuite.scala

@@ -20,12 +20,11 @@ package org.apache.spark.scheduler
 import scala.collection.mutable.{ArrayBuffer, HashSet, HashMap, Map}
 import scala.language.reflectiveCalls
 
+import org.mockito.Mockito.mock
 import org.scalatest.{BeforeAndAfter, FunSuiteLike}
 import org.scalatest.concurrent.Timeouts
 import org.scalatest.time.SpanSugar._
 
-import org.mockito.Mockito.mock
-
 import org.apache.spark._
 import org.apache.spark.rdd.RDD
 import org.apache.spark.scheduler.SchedulingMode.SchedulingMode