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Posted to commits@spark.apache.org by ma...@apache.org on 2014/03/19 20:47:02 UTC
git commit: Bugfixes/improvements to scheduler
Repository: spark
Updated Branches:
refs/heads/master 6112270c9 -> ab747d39d
Bugfixes/improvements to scheduler
Move the PR#517 of apache-incubator-spark to the apache-spark
Author: Mridul Muralidharan <mr...@gmail.com>
Closes #159 from mridulm/master and squashes the following commits:
5ff59c2 [Mridul Muralidharan] Change property in suite also
167fad8 [Mridul Muralidharan] Address review comments
9bda70e [Mridul Muralidharan] Address review comments, akwats add to failedExecutors
270d841 [Mridul Muralidharan] Address review comments
fa5d9f1 [Mridul Muralidharan] Bugfixes/improvements to scheduler : PR #517
Project: http://git-wip-us.apache.org/repos/asf/spark/repo
Commit: http://git-wip-us.apache.org/repos/asf/spark/commit/ab747d39
Tree: http://git-wip-us.apache.org/repos/asf/spark/tree/ab747d39
Diff: http://git-wip-us.apache.org/repos/asf/spark/diff/ab747d39
Branch: refs/heads/master
Commit: ab747d39ddc7c8a314ed2fb26548fc5652af0d74
Parents: 6112270
Author: Mridul Muralidharan <mr...@gmail.com>
Authored: Wed Mar 19 12:46:55 2014 -0700
Committer: Matei Zaharia <ma...@databricks.com>
Committed: Wed Mar 19 12:46:55 2014 -0700
----------------------------------------------------------------------
.../spark/scheduler/TaskSchedulerImpl.scala | 3 +-
.../apache/spark/scheduler/TaskSetManager.scala | 82 +++++++++++++-----
.../spark/scheduler/TaskSetManagerSuite.scala | 87 ++++++++++++++++++++
3 files changed, 152 insertions(+), 20 deletions(-)
----------------------------------------------------------------------
http://git-wip-us.apache.org/repos/asf/spark/blob/ab747d39/core/src/main/scala/org/apache/spark/scheduler/TaskSchedulerImpl.scala
----------------------------------------------------------------------
diff --git a/core/src/main/scala/org/apache/spark/scheduler/TaskSchedulerImpl.scala b/core/src/main/scala/org/apache/spark/scheduler/TaskSchedulerImpl.scala
index 23b0661..abff252 100644
--- a/core/src/main/scala/org/apache/spark/scheduler/TaskSchedulerImpl.scala
+++ b/core/src/main/scala/org/apache/spark/scheduler/TaskSchedulerImpl.scala
@@ -235,7 +235,8 @@ private[spark] class TaskSchedulerImpl(
taskIdToExecutorId(tid) = execId
activeExecutorIds += execId
executorsByHost(host) += execId
- availableCpus(i) -= 1
+ availableCpus(i) -= taskSet.CPUS_PER_TASK
+ assert (availableCpus(i) >= 0)
launchedTask = true
}
}
http://git-wip-us.apache.org/repos/asf/spark/blob/ab747d39/core/src/main/scala/org/apache/spark/scheduler/TaskSetManager.scala
----------------------------------------------------------------------
diff --git a/core/src/main/scala/org/apache/spark/scheduler/TaskSetManager.scala b/core/src/main/scala/org/apache/spark/scheduler/TaskSetManager.scala
index 5ea4557..a73343c 100644
--- a/core/src/main/scala/org/apache/spark/scheduler/TaskSetManager.scala
+++ b/core/src/main/scala/org/apache/spark/scheduler/TaskSetManager.scala
@@ -59,6 +59,15 @@ private[spark] class TaskSetManager(
// CPUs to request per task
val CPUS_PER_TASK = conf.getInt("spark.task.cpus", 1)
+ /*
+ * Sometimes if an executor is dead or in an otherwise invalid state, the driver
+ * does not realize right away leading to repeated task failures. If enabled,
+ * this temporarily prevents a task from re-launching on an executor where
+ * it just failed.
+ */
+ private val EXECUTOR_TASK_BLACKLIST_TIMEOUT =
+ conf.getLong("spark.scheduler.executorTaskBlacklistTime", 0L)
+
// Quantile of tasks at which to start speculation
val SPECULATION_QUANTILE = conf.getDouble("spark.speculation.quantile", 0.75)
val SPECULATION_MULTIPLIER = conf.getDouble("spark.speculation.multiplier", 1.5)
@@ -71,7 +80,9 @@ private[spark] class TaskSetManager(
val numTasks = tasks.length
val copiesRunning = new Array[Int](numTasks)
val successful = new Array[Boolean](numTasks)
- val numFailures = new Array[Int](numTasks)
+ private val numFailures = new Array[Int](numTasks)
+ // key is taskId, value is a Map of executor id to when it failed
+ private val failedExecutors = new HashMap[Int, HashMap[String, Long]]()
val taskAttempts = Array.fill[List[TaskInfo]](numTasks)(Nil)
var tasksSuccessful = 0
@@ -228,12 +239,18 @@ private[spark] class TaskSetManager(
* This method also cleans up any tasks in the list that have already
* been launched, since we want that to happen lazily.
*/
- private def findTaskFromList(list: ArrayBuffer[Int]): Option[Int] = {
- while (!list.isEmpty) {
- val index = list.last
- list.trimEnd(1)
- if (copiesRunning(index) == 0 && !successful(index)) {
- return Some(index)
+ private def findTaskFromList(execId: String, list: ArrayBuffer[Int]): Option[Int] = {
+ var indexOffset = list.size
+
+ while (indexOffset > 0) {
+ indexOffset -= 1
+ val index = list(indexOffset)
+ if (!executorIsBlacklisted(execId, index)) {
+ // This should almost always be list.trimEnd(1) to remove tail
+ list.remove(indexOffset)
+ if (copiesRunning(index) == 0 && !successful(index)) {
+ return Some(index)
+ }
}
}
None
@@ -245,6 +262,21 @@ private[spark] class TaskSetManager(
}
/**
+ * Is this re-execution of a failed task on an executor it already failed in before
+ * EXECUTOR_TASK_BLACKLIST_TIMEOUT has elapsed ?
+ */
+ private def executorIsBlacklisted(execId: String, taskId: Int): Boolean = {
+ if (failedExecutors.contains(taskId)) {
+ val failed = failedExecutors.get(taskId).get
+
+ return failed.contains(execId) &&
+ clock.getTime() - failed.get(execId).get < EXECUTOR_TASK_BLACKLIST_TIMEOUT
+ }
+
+ false
+ }
+
+ /**
* Return a speculative task for a given executor if any are available. The task should not have
* an attempt running on this host, in case the host is slow. In addition, the task should meet
* the given locality constraint.
@@ -254,10 +286,13 @@ private[spark] class TaskSetManager(
{
speculatableTasks.retain(index => !successful(index)) // Remove finished tasks from set
+ def canRunOnHost(index: Int): Boolean =
+ !hasAttemptOnHost(index, host) && !executorIsBlacklisted(execId, index)
+
if (!speculatableTasks.isEmpty) {
// Check for process-local or preference-less tasks; note that tasks can be process-local
// on multiple nodes when we replicate cached blocks, as in Spark Streaming
- for (index <- speculatableTasks if !hasAttemptOnHost(index, host)) {
+ for (index <- speculatableTasks if canRunOnHost(index)) {
val prefs = tasks(index).preferredLocations
val executors = prefs.flatMap(_.executorId)
if (prefs.size == 0 || executors.contains(execId)) {
@@ -268,7 +303,7 @@ private[spark] class TaskSetManager(
// Check for node-local tasks
if (TaskLocality.isAllowed(locality, TaskLocality.NODE_LOCAL)) {
- for (index <- speculatableTasks if !hasAttemptOnHost(index, host)) {
+ for (index <- speculatableTasks if canRunOnHost(index)) {
val locations = tasks(index).preferredLocations.map(_.host)
if (locations.contains(host)) {
speculatableTasks -= index
@@ -280,7 +315,7 @@ private[spark] class TaskSetManager(
// Check for rack-local tasks
if (TaskLocality.isAllowed(locality, TaskLocality.RACK_LOCAL)) {
for (rack <- sched.getRackForHost(host)) {
- for (index <- speculatableTasks if !hasAttemptOnHost(index, host)) {
+ for (index <- speculatableTasks if canRunOnHost(index)) {
val racks = tasks(index).preferredLocations.map(_.host).map(sched.getRackForHost)
if (racks.contains(rack)) {
speculatableTasks -= index
@@ -292,7 +327,7 @@ private[spark] class TaskSetManager(
// Check for non-local tasks
if (TaskLocality.isAllowed(locality, TaskLocality.ANY)) {
- for (index <- speculatableTasks if !hasAttemptOnHost(index, host)) {
+ for (index <- speculatableTasks if canRunOnHost(index)) {
speculatableTasks -= index
return Some((index, TaskLocality.ANY))
}
@@ -309,12 +344,12 @@ private[spark] class TaskSetManager(
private def findTask(execId: String, host: String, locality: TaskLocality.Value)
: Option[(Int, TaskLocality.Value)] =
{
- for (index <- findTaskFromList(getPendingTasksForExecutor(execId))) {
+ for (index <- findTaskFromList(execId, getPendingTasksForExecutor(execId))) {
return Some((index, TaskLocality.PROCESS_LOCAL))
}
if (TaskLocality.isAllowed(locality, TaskLocality.NODE_LOCAL)) {
- for (index <- findTaskFromList(getPendingTasksForHost(host))) {
+ for (index <- findTaskFromList(execId, getPendingTasksForHost(host))) {
return Some((index, TaskLocality.NODE_LOCAL))
}
}
@@ -322,19 +357,19 @@ private[spark] class TaskSetManager(
if (TaskLocality.isAllowed(locality, TaskLocality.RACK_LOCAL)) {
for {
rack <- sched.getRackForHost(host)
- index <- findTaskFromList(getPendingTasksForRack(rack))
+ index <- findTaskFromList(execId, getPendingTasksForRack(rack))
} {
return Some((index, TaskLocality.RACK_LOCAL))
}
}
// Look for no-pref tasks after rack-local tasks since they can run anywhere.
- for (index <- findTaskFromList(pendingTasksWithNoPrefs)) {
+ for (index <- findTaskFromList(execId, pendingTasksWithNoPrefs)) {
return Some((index, TaskLocality.PROCESS_LOCAL))
}
if (TaskLocality.isAllowed(locality, TaskLocality.ANY)) {
- for (index <- findTaskFromList(allPendingTasks)) {
+ for (index <- findTaskFromList(execId, allPendingTasks)) {
return Some((index, TaskLocality.ANY))
}
}
@@ -460,6 +495,7 @@ private[spark] class TaskSetManager(
logInfo("Ignorning task-finished event for TID " + tid + " because task " +
index + " has already completed successfully")
}
+ failedExecutors.remove(index)
maybeFinishTaskSet()
}
@@ -480,7 +516,7 @@ private[spark] class TaskSetManager(
logWarning("Lost TID %s (task %s:%d)".format(tid, taskSet.id, index))
}
var taskMetrics : TaskMetrics = null
- var failureReason = "unknown"
+ var failureReason: String = null
reason match {
case fetchFailed: FetchFailed =>
logWarning("Loss was due to fetch failure from " + fetchFailed.bmAddress)
@@ -488,9 +524,11 @@ private[spark] class TaskSetManager(
successful(index) = true
tasksSuccessful += 1
}
+ // Not adding to failed executors for FetchFailed.
isZombie = true
case TaskKilled =>
+ // Not adding to failed executors for TaskKilled.
logWarning("Task %d was killed.".format(tid))
case ef: ExceptionFailure =>
@@ -504,7 +542,8 @@ private[spark] class TaskSetManager(
return
}
val key = ef.description
- failureReason = "Exception failure: %s".format(ef.description)
+ failureReason = "Exception failure in TID %s on host %s: %s".format(
+ tid, info.host, ef.description)
val now = clock.getTime()
val (printFull, dupCount) = {
if (recentExceptions.contains(key)) {
@@ -533,11 +572,16 @@ private[spark] class TaskSetManager(
failureReason = "Lost result for TID %s on host %s".format(tid, info.host)
logWarning(failureReason)
- case _ => {}
+ case _ =>
+ failureReason = "TID %s on host %s failed for unknown reason".format(tid, info.host)
}
+ // always add to failed executors
+ failedExecutors.getOrElseUpdate(index, new HashMap[String, Long]()).
+ put(info.executorId, clock.getTime())
sched.dagScheduler.taskEnded(tasks(index), reason, null, null, info, taskMetrics)
addPendingTask(index)
if (!isZombie && state != TaskState.KILLED) {
+ assert (null != failureReason)
numFailures(index) += 1
if (numFailures(index) >= maxTaskFailures) {
logError("Task %s:%d failed %d times; aborting job".format(
http://git-wip-us.apache.org/repos/asf/spark/blob/ab747d39/core/src/test/scala/org/apache/spark/scheduler/TaskSetManagerSuite.scala
----------------------------------------------------------------------
diff --git a/core/src/test/scala/org/apache/spark/scheduler/TaskSetManagerSuite.scala b/core/src/test/scala/org/apache/spark/scheduler/TaskSetManagerSuite.scala
index 33cc758..73153d2 100644
--- a/core/src/test/scala/org/apache/spark/scheduler/TaskSetManagerSuite.scala
+++ b/core/src/test/scala/org/apache/spark/scheduler/TaskSetManagerSuite.scala
@@ -298,6 +298,93 @@ class TaskSetManagerSuite extends FunSuite with LocalSparkContext with Logging {
}
}
+ test("executors should be blacklisted after task failure, in spite of locality preferences") {
+ val rescheduleDelay = 300L
+ val conf = new SparkConf().
+ set("spark.scheduler.executorTaskBlacklistTime", rescheduleDelay.toString).
+ // dont wait to jump locality levels in this test
+ set("spark.locality.wait", "0")
+
+ sc = new SparkContext("local", "test", conf)
+ // two executors on same host, one on different.
+ val sched = new FakeTaskScheduler(sc, ("exec1", "host1"),
+ ("exec1.1", "host1"), ("exec2", "host2"))
+ // affinity to exec1 on host1 - which we will fail.
+ val taskSet = FakeTask.createTaskSet(1, Seq(TaskLocation("host1", "exec1")))
+ val clock = new FakeClock
+ val manager = new TaskSetManager(sched, taskSet, 4, clock)
+
+ {
+ val offerResult = manager.resourceOffer("exec1", "host1", 1, TaskLocality.PROCESS_LOCAL)
+ assert(offerResult.isDefined, "Expect resource offer to return a task")
+
+ assert(offerResult.get.index === 0)
+ assert(offerResult.get.executorId === "exec1")
+
+ // Cause exec1 to fail : failure 1
+ manager.handleFailedTask(offerResult.get.taskId, TaskState.FINISHED, TaskResultLost)
+ assert(!sched.taskSetsFailed.contains(taskSet.id))
+
+ // Ensure scheduling on exec1 fails after failure 1 due to blacklist
+ assert(manager.resourceOffer("exec1", "host1", 1, TaskLocality.PROCESS_LOCAL).isEmpty)
+ assert(manager.resourceOffer("exec1", "host1", 1, TaskLocality.NODE_LOCAL).isEmpty)
+ assert(manager.resourceOffer("exec1", "host1", 1, TaskLocality.RACK_LOCAL).isEmpty)
+ assert(manager.resourceOffer("exec1", "host1", 1, TaskLocality.ANY).isEmpty)
+ }
+
+ // Run the task on exec1.1 - should work, and then fail it on exec1.1
+ {
+ val offerResult = manager.resourceOffer("exec1.1", "host1", 1, TaskLocality.NODE_LOCAL)
+ assert(offerResult.isDefined,
+ "Expect resource offer to return a task for exec1.1, offerResult = " + offerResult)
+
+ assert(offerResult.get.index === 0)
+ assert(offerResult.get.executorId === "exec1.1")
+
+ // Cause exec1.1 to fail : failure 2
+ manager.handleFailedTask(offerResult.get.taskId, TaskState.FINISHED, TaskResultLost)
+ assert(!sched.taskSetsFailed.contains(taskSet.id))
+
+ // Ensure scheduling on exec1.1 fails after failure 2 due to blacklist
+ assert(manager.resourceOffer("exec1.1", "host1", 1, TaskLocality.NODE_LOCAL).isEmpty)
+ }
+
+ // Run the task on exec2 - should work, and then fail it on exec2
+ {
+ val offerResult = manager.resourceOffer("exec2", "host2", 1, TaskLocality.ANY)
+ assert(offerResult.isDefined, "Expect resource offer to return a task")
+
+ assert(offerResult.get.index === 0)
+ assert(offerResult.get.executorId === "exec2")
+
+ // Cause exec2 to fail : failure 3
+ manager.handleFailedTask(offerResult.get.taskId, TaskState.FINISHED, TaskResultLost)
+ assert(!sched.taskSetsFailed.contains(taskSet.id))
+
+ // Ensure scheduling on exec2 fails after failure 3 due to blacklist
+ assert(manager.resourceOffer("exec2", "host2", 1, TaskLocality.ANY).isEmpty)
+ }
+
+ // After reschedule delay, scheduling on exec1 should be possible.
+ clock.advance(rescheduleDelay)
+
+ {
+ val offerResult = manager.resourceOffer("exec1", "host1", 1, TaskLocality.PROCESS_LOCAL)
+ assert(offerResult.isDefined, "Expect resource offer to return a task")
+
+ assert(offerResult.get.index === 0)
+ assert(offerResult.get.executorId === "exec1")
+
+ assert(manager.resourceOffer("exec1", "host1", 1, TaskLocality.PROCESS_LOCAL).isEmpty)
+
+ // Cause exec1 to fail : failure 4
+ manager.handleFailedTask(offerResult.get.taskId, TaskState.FINISHED, TaskResultLost)
+ }
+
+ // we have failed the same task 4 times now : task id should now be in taskSetsFailed
+ assert(sched.taskSetsFailed.contains(taskSet.id))
+ }
+
def createTaskResult(id: Int): DirectTaskResult[Int] = {
val valueSer = SparkEnv.get.serializer.newInstance()
new DirectTaskResult[Int](valueSer.serialize(id), mutable.Map.empty, new TaskMetrics)