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https://issues.apache.org/jira/browse/YARN-11697?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17848072#comment-17848072
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Wilfred Spiegelenburg commented on YARN-11697:
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The stack trace does not correspond to hadoop 3.2.1:
[FairScheduler.java:757|https://github.com/apache/hadoop/blob/branch-3.2.1/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/fair/FairScheduler.java#L757]
That points to this line in hadoop 3.2.1 which is part of
completedContainerInternal
{code:java}
755 application.containerCompleted(rmContainer, containerStatus, event);
756 if (node != null) {
757 node.releaseContainer(rmContainer.getContainerId(), false);
758 } else if (LOG.isDebugEnabled()) {
759 LOG.debug("Skipping container release on removed node: " + nodeID);
760 } {code}
The comment in the moveApplication around locking the app attempt are for
scheduling. An application could be scheduled while being moved and that needs
to be stopped. The remove of an application attempt takes a write lock on the
scheduler itself. Same as the move does. So a moveApplication and
removeApplicationAttempt cannot happen at the same time. they both need that
lock and are serialised.
I think you are looking at the wrong thing and a move is not involved.
> Fix fair scheduler race condition in removeApplicationAttempt and
> moveApplication
> ---------------------------------------------------------------------------------
>
> Key: YARN-11697
> URL: https://issues.apache.org/jira/browse/YARN-11697
> Project: Hadoop YARN
> Issue Type: Bug
> Affects Versions: 3.2.1
> Reporter: Syed Shameerur Rahman
> Assignee: Syed Shameerur Rahman
> Priority: Major
>
> For Hadoop version 3.2.1, the ResourceManager (RM) restarts frequently with
> the following exception
> {code:java}
> 2024-03-11 04:41:29,329 FATAL org.apache.hadoop.yarn.event.EventDispatcher
> (SchedulerEventDispatcher:Event Processor): Error in handling event type
> APP_ATTEMPT_REMOVED to the Event Dispatcher
> java.lang.IllegalStateException: Given app to remove
> appattempt_1706879498319_86660_000001 Alloc: <memory:0, vCores:0> does not
> exist in queue [root, demand=<memory:10826752, vCores:2101>,
> running=<memory:99328, vCores:17>, share=<memory:6201984, vCores:0>, w=1.0]
> at
> org.apache.hadoop.yarn.server.resourcemanager.scheduler.fair.FSLeafQueue.removeApp(FSLeafQueue.java:121)
> at
> org.apache.hadoop.yarn.server.resourcemanager.scheduler.fair.FairScheduler.removeApplicationAttempt(FairScheduler.java:757)
> at
> org.apache.hadoop.yarn.server.resourcemanager.scheduler.fair.FairScheduler.handle(FairScheduler.java:1378)
> at
> org.apache.hadoop.yarn.server.resourcemanager.scheduler.fair.FairScheduler.handle(FairScheduler.java:139)
> at
> org.apache.hadoop.yarn.event.EventDispatcher$EventProcessor.run(EventDispatcher.java:66)
> at java.lang.Thread.run(Thread.java:750)
> {code}
> The exception seems similar to the one mentioned in YARN-5136, but it looks
> like there is still some edge cases not covered by YARN-5136.
> 1. On deeper look, i could see that as mentioned in the comment here. if a
> call for a moveApplication and removeApplicationAttempt for the same attempt
> are processed in short succession the application attempt will still contain
> a queue reference but is already removed from the list of applications for
> the queue.
> 2. This can happen when
> [moveApplication|https://github.com/apache/hadoop/blob/trunk/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/fair/FairScheduler.java#L1908]
> removes the appAttempt from the queue and
> [removeApplicationAttempt|https://github.com/apache/hadoop/blob/trunk/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/fair/FairScheduler.java#L707]
> also tries to remove the same appAttempt from the queue.
> 3. On further checking, i could see that before doing
> [moveApplication|https://github.com/apache/hadoop/blob/trunk/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/fair/FairScheduler.java#L1779]
> writeLock on appAttempt is taken where as for
> [removeApplicationAttempt|https://github.com/apache/hadoop/blob/trunk/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/fair/FairScheduler.java#L665]
> , i don't see any writelock being taken which can result in race condition
> if same appAttempt is being processed.
> 4. Additionally as mentioned in the comment here when such scenario occurs
> ideally we should not take down RM.
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