[
https://issues.apache.org/jira/browse/YARN-2910?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14235841#comment-14235841
]
Ray Chiang commented on YARN-2910:
----------------------------------
I get the same error for TestFSLeafQueue in my tree:
Running
org.apache.hadoop.yarn.server.resourcemanager.scheduler.fair.TestFSLeafQueue
Tests run: 4, Failures: 0, Errors: 1, Skipped: 0, Time elapsed: 2.185 sec <<<
FAILURE! - in
org.apache.hadoop.yarn.server.resourcemanager.scheduler.fair.TestFSLeafQueue
testConcurrentAccess(org.apache.hadoop.yarn.server.resourcemanager.scheduler.fair.TestFSLeafQueue)
Time elapsed: 0.116 sec <<< ERROR!
java.lang.NullPointerException: null
at
org.apache.hadoop.yarn.server.resourcemanager.scheduler.fair.FSQueueMetrics.setMinShare(FSQueueMetrics.java:75)
at
org.apache.hadoop.yarn.server.resourcemanager.scheduler.fair.FSQueue.<init>(FSQueue.java:64)
at
org.apache.hadoop.yarn.server.resourcemanager.scheduler.fair.FSLeafQueue.<init>(FSLeafQueue.java:67)
at
org.apache.hadoop.yarn.server.resourcemanager.scheduler.fair.TestFSLeafQueue.testConcurrentAccess(TestFSLeafQueue.java:243)
> FSLeafQueue can throw ConcurrentModificationException
> -----------------------------------------------------
>
> Key: YARN-2910
> URL: https://issues.apache.org/jira/browse/YARN-2910
> Project: Hadoop YARN
> Issue Type: Bug
> Components: fairscheduler
> Affects Versions: 2.5.0
> Reporter: Wilfred Spiegelenburg
> Assignee: Wilfred Spiegelenburg
> Attachments: FSLeafQueue_concurrent_exception.txt, YARN-2910.1.patch,
> YARN-2910.patch
>
>
> The list that maintains the runnable and the non runnable apps are a standard
> ArrayList but there is no guarantee that it will only be manipulated by one
> thread in the system. This can lead to the following exception:
> {noformat}
> 2014-11-12 02:29:01,169 ERROR [RMCommunicator Allocator]
> org.apache.hadoop.mapreduce.v2.app.rm.RMContainerAllocator: ERROR IN
> CONTACTING RM.
> java.util.ConcurrentModificationException:
> java.util.ConcurrentModificationException
> at java.util.ArrayList$Itr.checkForComodification(ArrayList.java:859)
> at java.util.ArrayList$Itr.next(ArrayList.java:831)
> at
> org.apache.hadoop.yarn.server.resourcemanager.scheduler.fair.FSLeafQueue.getResourceUsage(FSLeafQueue.java:147)
> at
> org.apache.hadoop.yarn.server.resourcemanager.scheduler.fair.FSAppAttempt.getHeadroom(FSAppAttempt.java:180)
> at
> org.apache.hadoop.yarn.server.resourcemanager.scheduler.fair.FairScheduler.allocate(FairScheduler.java:923)
> at
> org.apache.hadoop.yarn.server.resourcemanager.ApplicationMasterService.allocate(ApplicationMasterService.java:516)
> {noformat}
> Full stack trace in the attached file.
> We should guard against that by using a thread safe version from
> java.util.concurrent.CopyOnWriteArrayList
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
