-
Notifications
You must be signed in to change notification settings - Fork 28.3k
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
- Loading branch information
1 parent
124d396
commit 9e6faa2
Showing
4 changed files
with
247 additions
and
41 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
176 changes: 176 additions & 0 deletions
176
...ctor/connect/client/jvm/src/main/scala/org/apache/spark/sql/internal/ContextCleaner.scala
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,176 @@ | ||
| /* | ||
| * 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.sql.internal | ||
|
|
||
| import java.lang.ref.{ReferenceQueue, WeakReference} | ||
| import java.util.Collections | ||
| import java.util.concurrent.{ConcurrentHashMap, ScheduledExecutorService, ScheduledThreadPoolExecutor, TimeUnit} | ||
|
|
||
| import com.google.common.util.concurrent.ThreadFactoryBuilder | ||
|
|
||
| import org.apache.spark.connect.proto | ||
| import org.apache.spark.internal.Logging | ||
| import org.apache.spark.sql.SparkSession | ||
|
|
||
| /** | ||
| * Classes that represent cleaning tasks. | ||
| */ | ||
| private sealed trait CleanupTask | ||
| private case class CleanupCachedRemoteRelation(dfID: String) extends CleanupTask | ||
|
|
||
| /** | ||
| * A WeakReference associated with a CleanupTask. | ||
| * | ||
| * When the referent object becomes only weakly reachable, the corresponding | ||
| * CleanupTaskWeakReference is automatically added to the given reference queue. | ||
| */ | ||
| private class CleanupTaskWeakReference( | ||
| val task: CleanupTask, | ||
| referent: AnyRef, | ||
| referenceQueue: ReferenceQueue[AnyRef]) | ||
| extends WeakReference(referent, referenceQueue) | ||
|
|
||
| /** | ||
| * An asynchronous cleaner for objects. | ||
| * | ||
| * This maintains a weak reference for each CashRemoteRelation, etc. of interest, to be processed | ||
| * when the associated object goes out of scope of the application. Actual cleanup is performed in | ||
| * a separate daemon thread. | ||
| */ | ||
| private[spark] class ContextCleaner(session: SparkSession) extends Logging { | ||
|
|
||
| /** | ||
| * How often (seconds) to trigger a garbage collection in this JVM. This context cleaner | ||
| * triggers cleanups only when weak references are garbage collected. In long-running | ||
| * applications with large driver JVMs, where there is little memory pressure on the driver, | ||
| * this may happen very occasionally or not at all. Not cleaning at all may lead to executors | ||
| * running out of disk space after a while. | ||
| */ | ||
| private val periodicGCInterval: Long = 30 * 60 | ||
| private val refQueuePollTimeout: Long = 100 | ||
|
|
||
| /** | ||
| * A buffer to ensure that `CleanupTaskWeakReference`s are not garbage collected as long as they | ||
| * have not been handled by the reference queue. | ||
| */ | ||
| private val referenceBuffer = | ||
| Collections.newSetFromMap[CleanupTaskWeakReference](new ConcurrentHashMap) | ||
|
|
||
| private val referenceQueue = new ReferenceQueue[AnyRef] | ||
|
|
||
| private val cleaningThread = new Thread() { override def run(): Unit = keepCleaning() } | ||
|
|
||
| private val periodicGCService: ScheduledExecutorService = | ||
| ContextCleaner.newDaemonSingleThreadScheduledExecutor( | ||
| "spark-connect-context-cleaner-periodic-gc") | ||
|
|
||
| @volatile private var started = false | ||
| @volatile private var stopped = false | ||
|
|
||
| /** Start the cleaner. */ | ||
| def start(): Unit = { | ||
| cleaningThread.setDaemon(true) | ||
| cleaningThread.setName("Spark Connect Context Cleaner") | ||
| cleaningThread.start() | ||
| periodicGCService.scheduleAtFixedRate( | ||
| () => System.gc(), | ||
| periodicGCInterval, | ||
| periodicGCInterval, | ||
| TimeUnit.SECONDS) | ||
| } | ||
|
|
||
| /** | ||
| * Stop the cleaning thread and wait until the thread has finished running its current task. | ||
| */ | ||
| def stop(): Unit = { | ||
| stopped = true | ||
| // Interrupt the cleaning thread, but wait until the current task has finished before | ||
| // doing so. This guards against the race condition where a cleaning thread may | ||
| // potentially clean similarly named variables created by a different SparkSession. | ||
| synchronized { | ||
| cleaningThread.interrupt() | ||
| } | ||
| cleaningThread.join() | ||
| periodicGCService.shutdown() | ||
| } | ||
|
|
||
| /** Register a CachedRemoteRelation for cleanup when it is garbage collected. */ | ||
| def registerCachedRemoteRelationForCleanup(relation: proto.CachedRemoteRelation): Unit = { | ||
| registerForCleanup(relation, CleanupCachedRemoteRelation(relation.getRelationId)) | ||
| } | ||
|
|
||
| /** Register an object for cleanup. */ | ||
| private def registerForCleanup(objectForCleanup: AnyRef, task: CleanupTask): Unit = { | ||
| if (!started) { | ||
| // Lazily starts when the first cleanup is registered. | ||
| start() | ||
| started = true | ||
| } | ||
| referenceBuffer.add(new CleanupTaskWeakReference(task, objectForCleanup, referenceQueue)) | ||
| } | ||
|
|
||
| /** Keep cleaning objects. */ | ||
| private def keepCleaning(): Unit = { | ||
| while (!stopped && !session.client.channel.isShutdown) { | ||
| try { | ||
| val reference = Option(referenceQueue.remove(refQueuePollTimeout)) | ||
| .map(_.asInstanceOf[CleanupTaskWeakReference]) | ||
| // Synchronize here to avoid being interrupted on stop() | ||
| synchronized { | ||
| reference.foreach { ref => | ||
| logDebug("Got cleaning task " + ref.task) | ||
| referenceBuffer.remove(ref) | ||
| ref.task match { | ||
| case CleanupCachedRemoteRelation(dfID) => | ||
| doCleanupCachedRemoteRelation(dfID) | ||
| } | ||
| } | ||
| } | ||
| } catch { | ||
| case e: Throwable => logError("Error in cleaning thread", e) | ||
| } | ||
| } | ||
| } | ||
|
|
||
| /** Perform CleanupCachedRemoteRelation cleanup. */ | ||
| private[spark] def doCleanupCachedRemoteRelation(dfID: String): Unit = { | ||
| session.execute { | ||
| session.newCommand { builder => | ||
| builder.getRemoveCachedRemoteRelationCommandBuilder | ||
| .setRelation(proto.CachedRemoteRelation.newBuilder().setRelationId(dfID).build()) | ||
| } | ||
| } | ||
| } | ||
| } | ||
|
|
||
| private object ContextCleaner { | ||
|
|
||
| /** | ||
| * Wrapper over ScheduledThreadPoolExecutor the pool with daemon threads. | ||
| */ | ||
| private def newDaemonSingleThreadScheduledExecutor( | ||
| threadName: String): ScheduledExecutorService = { | ||
| val threadFactory = | ||
| new ThreadFactoryBuilder().setDaemon(true).setNameFormat(threadName).build() | ||
| val executor = new ScheduledThreadPoolExecutor(1, threadFactory) | ||
| // By default, a cancelled task is not automatically removed from the work queue until its delay | ||
| // elapses. We have to enable it manually. | ||
| executor.setRemoveOnCancelPolicy(true) | ||
| executor | ||
| } | ||
| } |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters