Return-Path: X-Original-To: apmail-hadoop-yarn-issues-archive@minotaur.apache.org Delivered-To: apmail-hadoop-yarn-issues-archive@minotaur.apache.org Received: from mail.apache.org (hermes.apache.org [140.211.11.3]) by minotaur.apache.org (Postfix) with SMTP id 7D49BC33E for ; Fri, 5 Dec 2014 22:35:13 +0000 (UTC) Received: (qmail 88358 invoked by uid 500); 5 Dec 2014 22:35:13 -0000 Delivered-To: apmail-hadoop-yarn-issues-archive@hadoop.apache.org Received: (qmail 88310 invoked by uid 500); 5 Dec 2014 22:35:13 -0000 Mailing-List: contact yarn-issues-help@hadoop.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: yarn-issues@hadoop.apache.org Delivered-To: mailing list yarn-issues@hadoop.apache.org Received: (qmail 88298 invoked by uid 99); 5 Dec 2014 22:35:13 -0000 Received: from arcas.apache.org (HELO arcas.apache.org) (140.211.11.28) by apache.org (qpsmtpd/0.29) with ESMTP; Fri, 05 Dec 2014 22:35:13 +0000 Date: Fri, 5 Dec 2014 22:35:13 +0000 (UTC) From: "Tsuyoshi OZAWA (JIRA)" To: yarn-issues@hadoop.apache.org Message-ID: In-Reply-To: References: Subject: [jira] [Commented] (YARN-2910) FSLeafQueue can throw ConcurrentModificationException MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-JIRA-FingerPrint: 30527f35849b9dde25b450d4833f0394 [ https://issues.apache.org/jira/browse/YARN-2910?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14236234#comment-14236234 ] Tsuyoshi OZAWA commented on YARN-2910: -------------------------------------- The fix itself looks good to me. One concern is that the test passes without the fix on my local. > 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-2910.2.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)