[ https://issues.apache.org/jira/browse/YARN-2910?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14239123#comment-14239123 ]
Hadoop QA commented on YARN-2910: --------------------------------- {color:red}-1 overall{color}. Here are the results of testing the latest attachment http://issues.apache.org/jira/secure/attachment/12685948/YARN-2910.7.patch against trunk revision db73cc9. {color:green}+1 @author{color}. The patch does not contain any @author tags. {color:green}+1 tests included{color}. The patch appears to include 1 new or modified test files. {color:green}+1 javac{color}. The applied patch does not increase the total number of javac compiler warnings. {color:green}+1 javadoc{color}. There were no new javadoc warning messages. {color:green}+1 eclipse:eclipse{color}. The patch built with eclipse:eclipse. {color:red}-1 findbugs{color}. The patch appears to introduce 1 new Findbugs (version 2.0.3) warnings. {color:green}+1 release audit{color}. The applied patch does not increase the total number of release audit warnings. {color:red}-1 core tests{color}. The patch failed these unit tests in hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager: org.apache.hadoop.yarn.server.resourcemanager.TestWorkPreservingRMRestart {color:green}+1 contrib tests{color}. The patch passed contrib unit tests. Test results: https://builds.apache.org/job/PreCommit-YARN-Build/6054//testReport/ Findbugs warnings: https://builds.apache.org/job/PreCommit-YARN-Build/6054//artifact/patchprocess/newPatchFindbugsWarningshadoop-yarn-server-resourcemanager.html Console output: https://builds.apache.org/job/PreCommit-YARN-Build/6054//console This message is automatically generated. > 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, 2.6.0, 2.5.1, 2.5.2 > Reporter: Wilfred Spiegelenburg > Assignee: Wilfred Spiegelenburg > Attachments: FSLeafQueue_concurrent_exception.txt, > YARN-2910.004.patch, YARN-2910.1.patch, YARN-2910.2.patch, YARN-2910.3.patch, > YARN-2910.4.patch, YARN-2910.5.patch, YARN-2910.6.patch, YARN-2910.7.patch, > YARN-2910.8.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)