From 2a4ed10210f9ee32f472e2465094d88561c0ff18 Mon Sep 17 00:00:00 2001 From: Matei Zaharia Date: Thu, 15 Aug 2013 17:22:49 -0700 Subject: Address some review comments: - When a resourceOffers() call has multiple offers, force the TaskSets to consider them in increasing order of locality levels so that they get a chance to launch stuff locally across all offers - Simplify ClusterScheduler.prioritizeContainers - Add docs on the new configuration options --- .../spark/scheduler/cluster/ClusterScheduler.scala | 21 +++++++-------- .../scheduler/cluster/ClusterTaskSetManager.scala | 17 ++++++++---- .../spark/scheduler/cluster/TaskSetManager.scala | 6 ++++- .../spark/scheduler/local/LocalScheduler.scala | 3 +-- .../scheduler/local/LocalTaskSetManager.scala | 6 ++++- .../scheduler/cluster/ClusterSchedulerSuite.scala | 8 ++++-- docs/configuration.md | 30 ++++++++++++++++++++-- 7 files changed, 68 insertions(+), 23 deletions(-) diff --git a/core/src/main/scala/spark/scheduler/cluster/ClusterScheduler.scala b/core/src/main/scala/spark/scheduler/cluster/ClusterScheduler.scala index 028f4d3283..e88edc5b2a 100644 --- a/core/src/main/scala/spark/scheduler/cluster/ClusterScheduler.scala +++ b/core/src/main/scala/spark/scheduler/cluster/ClusterScheduler.scala @@ -184,27 +184,29 @@ private[spark] class ClusterScheduler(val sc: SparkContext) } } - // Build a list of tasks to assign to each slave + // Build a list of tasks to assign to each worker val tasks = offers.map(o => new ArrayBuffer[TaskDescription](o.cores)) val availableCpus = offers.map(o => o.cores).toArray - val sortedTaskSetQueue = rootPool.getSortedTaskSetQueue() - for (manager <- sortedTaskSetQueue) { + val sortedTaskSets = rootPool.getSortedTaskSetQueue() + for (taskSet <- sortedTaskSets) { logDebug("parentName: %s, name: %s, runningTasks: %s".format( - manager.parent.name, manager.name, manager.runningTasks)) + taskSet.parent.name, taskSet.name, taskSet.runningTasks)) } + // Take each TaskSet in our scheduling order, and then offer it each node in increasing order + // of locality levels so that it gets a chance to launch local tasks on all of them. var launchedTask = false - for (manager <- sortedTaskSetQueue; offer <- offers) { + for (taskSet <- sortedTaskSets; maxLocality <- TaskLocality.values) { do { launchedTask = false for (i <- 0 until offers.size) { val execId = offers(i).executorId val host = offers(i).host - for (task <- manager.resourceOffer(execId, host, availableCpus(i))) { + for (task <- taskSet.resourceOffer(execId, host, availableCpus(i), maxLocality)) { tasks(i) += task val tid = task.taskId - taskIdToTaskSetId(tid) = manager.taskSet.id - taskSetTaskIds(manager.taskSet.id) += tid + taskIdToTaskSetId(tid) = taskSet.taskSet.id + taskSetTaskIds(taskSet.taskSet.id) += tid taskIdToExecutorId(tid) = execId activeExecutorIds += execId executorsByHost(host) += execId @@ -402,8 +404,7 @@ object ClusterScheduler { // order keyList based on population of value in map val keyList = _keyList.sortWith( - // TODO(matei): not sure why we're using getOrElse if keyList = map.keys... see if it matters - (left, right) => map.get(left).getOrElse(Set()).size > map.get(right).getOrElse(Set()).size + (left, right) => map(left).size > map(right).size ) val retval = new ArrayBuffer[T](keyList.size * 2) diff --git a/core/src/main/scala/spark/scheduler/cluster/ClusterTaskSetManager.scala b/core/src/main/scala/spark/scheduler/cluster/ClusterTaskSetManager.scala index 5316a7aed1..91de25254c 100644 --- a/core/src/main/scala/spark/scheduler/cluster/ClusterTaskSetManager.scala +++ b/core/src/main/scala/spark/scheduler/cluster/ClusterTaskSetManager.scala @@ -43,7 +43,7 @@ private[spark] class ClusterTaskSetManager(sched: ClusterScheduler, val taskSet: extends TaskSetManager with Logging { // CPUs to request per task - val CPUS_PER_TASK = System.getProperty("spark.task.cpus", "1").toDouble + val CPUS_PER_TASK = System.getProperty("spark.task.cpus", "1").toInt // Maximum times a task is allowed to fail before failing the job val MAX_TASK_FAILURES = System.getProperty("spark.task.maxFailures", "4").toInt @@ -325,15 +325,22 @@ private[spark] class ClusterTaskSetManager(sched: ClusterScheduler, val taskSet: /** * Respond to an offer of a single slave from the scheduler by finding a task */ - override def resourceOffer(execId: String, host: String, availableCpus: Double) + override def resourceOffer( + execId: String, + host: String, + availableCpus: Int, + maxLocality: TaskLocality.TaskLocality) : Option[TaskDescription] = { if (tasksFinished < numTasks && availableCpus >= CPUS_PER_TASK) { val curTime = System.currentTimeMillis() - val locality = getAllowedLocalityLevel(curTime) + var allowedLocality = getAllowedLocalityLevel(curTime) + if (allowedLocality > maxLocality) { + allowedLocality = maxLocality // We're not allowed to search for farther-away tasks + } - findTask(execId, host, locality) match { + findTask(execId, host, allowedLocality) match { case Some((index, taskLocality)) => { // Found a task; do some bookkeeping and return a task description val task = tasks(index) @@ -347,7 +354,7 @@ private[spark] class ClusterTaskSetManager(sched: ClusterScheduler, val taskSet: taskInfos(taskId) = info taskAttempts(index) = info :: taskAttempts(index) // Update our locality level for delay scheduling - currentLocalityIndex = getLocalityIndex(locality) + currentLocalityIndex = getLocalityIndex(allowedLocality) lastLaunchTime = curTime // Serialize and return the task val startTime = System.currentTimeMillis() diff --git a/core/src/main/scala/spark/scheduler/cluster/TaskSetManager.scala b/core/src/main/scala/spark/scheduler/cluster/TaskSetManager.scala index 277654edc0..5ab6ab9aad 100644 --- a/core/src/main/scala/spark/scheduler/cluster/TaskSetManager.scala +++ b/core/src/main/scala/spark/scheduler/cluster/TaskSetManager.scala @@ -29,7 +29,11 @@ private[spark] trait TaskSetManager extends Schedulable { def taskSet: TaskSet - def resourceOffer(execId: String, hostPort: String, availableCpus: Double) + def resourceOffer( + execId: String, + host: String, + availableCpus: Int, + maxLocality: TaskLocality.TaskLocality) : Option[TaskDescription] def statusUpdate(tid: Long, state: TaskState, serializedData: ByteBuffer) diff --git a/core/src/main/scala/spark/scheduler/local/LocalScheduler.scala b/core/src/main/scala/spark/scheduler/local/LocalScheduler.scala index a4f5f46777..5be4dbd9f0 100644 --- a/core/src/main/scala/spark/scheduler/local/LocalScheduler.scala +++ b/core/src/main/scala/spark/scheduler/local/LocalScheduler.scala @@ -141,8 +141,7 @@ private[spark] class LocalScheduler(threads: Int, val maxFailures: Int, val sc: for (manager <- sortedTaskSetQueue) { do { launchTask = false - // TODO(matei): don't pass null here? - manager.resourceOffer(null, null, freeCpuCores) match { + manager.resourceOffer(null, null, freeCpuCores, null) match { case Some(task) => tasks += task taskIdToTaskSetId(task.taskId) = manager.taskSet.id diff --git a/core/src/main/scala/spark/scheduler/local/LocalTaskSetManager.scala b/core/src/main/scala/spark/scheduler/local/LocalTaskSetManager.scala index 698c777bec..3ef636ff07 100644 --- a/core/src/main/scala/spark/scheduler/local/LocalTaskSetManager.scala +++ b/core/src/main/scala/spark/scheduler/local/LocalTaskSetManager.scala @@ -98,7 +98,11 @@ private[spark] class LocalTaskSetManager(sched: LocalScheduler, val taskSet: Tas return None } - override def resourceOffer(execId: String, host: String, availableCpus: Double) + override def resourceOffer( + execId: String, + host: String, + availableCpus: Int, + maxLocality: TaskLocality.TaskLocality) : Option[TaskDescription] = { SparkEnv.set(sched.env) diff --git a/core/src/test/scala/spark/scheduler/cluster/ClusterSchedulerSuite.scala b/core/src/test/scala/spark/scheduler/cluster/ClusterSchedulerSuite.scala index 8618009ea6..aeeed14786 100644 --- a/core/src/test/scala/spark/scheduler/cluster/ClusterSchedulerSuite.scala +++ b/core/src/test/scala/spark/scheduler/cluster/ClusterSchedulerSuite.scala @@ -72,7 +72,11 @@ class DummyTaskSetManager( override def executorLost(executorId: String, host: String): Unit = { } - override def resourceOffer(execId: String, host: String, availableCpus: Double) + override def resourceOffer( + execId: String, + host: String, + availableCpus: Int, + maxLocality: TaskLocality.TaskLocality) : Option[TaskDescription] = { if (tasksFinished + runningTasks < numTasks) { @@ -120,7 +124,7 @@ class ClusterSchedulerSuite extends FunSuite with LocalSparkContext with Logging logInfo("parentName:%s, parent running tasks:%d, name:%s,runningTasks:%d".format(manager.parent.name, manager.parent.runningTasks, manager.name, manager.runningTasks)) } for (taskSet <- taskSetQueue) { - taskSet.resourceOffer("execId_1", "hostname_1", 1) match { + taskSet.resourceOffer("execId_1", "hostname_1", 1, TaskLocality.ANY) match { case Some(task) => return taskSet.stageId case None => {} diff --git a/docs/configuration.md b/docs/configuration.md index 99624a44aa..dff08a06f5 100644 --- a/docs/configuration.md +++ b/docs/configuration.md @@ -243,8 +243,34 @@ Apart from these, the following properties are also available, and may be useful 3000 Number of milliseconds to wait to launch a data-local task before giving up and launching it - in a non-data-local location. You should increase this if your tasks are long and you are seeing - poor data locality, but the default generally works well. + on a less-local node. The same wait will be used to step through multiple locality levels + (process-local, node-local, rack-local and then any). It is also possible to customize the + waiting time for each level by setting spark.locality.wait.node, etc. + You should increase this setting if your tasks are long and see poor locality, but the + default usually works well. + + + + spark.locality.wait.process + spark.locality.wait + + Customize the locality wait for process locality. This affects tasks that attempt to access + cached data in a particular executor process. + + + + spark.locality.wait.node + spark.locality.wait + + Customize the locality wait for node locality. For example, you can set this to 0 to skip + node locality and search immediately for rack locality (if your cluster has rack information). + + + + spark.locality.wait.rack + spark.locality.wait + + Customize the locality wait for rack locality. -- cgit v1.2.3