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Hudson commented on HADOOP-4116: -------------------------------- Integrated in Hadoop-trunk #615 (See [http://hudson.zones.apache.org/hudson/job/Hadoop-trunk/615/]) > 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.