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Hadoop QA commented on HADOOP-4116: ----------------------------------- -1 overall. Here are the results of testing the latest attachment http://issues.apache.org/jira/secure/attachment/12390875/balancerRM2.patch against trunk revision 698721. +1 @author. The patch does not contain any @author tags. +1 tests included. The patch appears to include 3 new or modified tests. +1 javadoc. The javadoc tool did not generate any warning messages. +1 javac. The applied patch does not increase the total number of javac compiler warnings. +1 findbugs. The patch does not introduce any new Findbugs warnings. +1 Eclipse classpath. The patch retains Eclipse classpath integrity. -1 core tests. The patch failed core unit tests. +1 contrib tests. The patch passed contrib unit tests. Test results: http://hudson.zones.apache.org/hudson/job/Hadoop-Patch/3365/testReport/ Findbugs warnings: http://hudson.zones.apache.org/hudson/job/Hadoop-Patch/3365/artifact/trunk/build/test/findbugs/newPatchFindbugsWarnings.html Checkstyle results: http://hudson.zones.apache.org/hudson/job/Hadoop-Patch/3365/artifact/trunk/build/test/checkstyle-errors.html Console output: http://hudson.zones.apache.org/hudson/job/Hadoop-Patch/3365/console This message is automatically generated. > Balancer should provide better resource management > -------------------------------------------------- > > Key: HADOOP-4116 > URL: https://issues.apache.org/jira/browse/HADOOP-4116 > Project: Hadoop Core > Issue Type: Bug > Components: dfs > Affects Versions: 0.17.0 > Reporter: Raghu Angadi > Assignee: Hairong Kuang > Priority: Blocker > Fix For: 0.18.2, 0.19.0 > > Attachments: balancerRM.patch, balancerRM1.patch, > balancerRM2-b18.patch, balancerRM2.patch > > > The number of threads are currently limited on datanodes. Once these threads > are occupied, DataNode does not accept any more requests (DOS). Recently we > saw a case where most of the 256 threads were waiting in > {{DataXceiver.replaceBlock()}} trying to acquire {{balancingSem}}. Since > rebalancing is (heavily) throttled, I would think this would be the common > case. > These operations waiting for active rebalancing threads to finish need not > take up a thread. -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online.