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Miomir Boljanovic commented on MAPREDUCE-4229: ---------------------------------------------- Sorry, this has been a hectic week for me too. Unfortunately, I don't have any figures to share yet but will try to capture some heap dumps over the weekend. > Intern counter names in the JT > ------------------------------ > > Key: MAPREDUCE-4229 > URL: https://issues.apache.org/jira/browse/MAPREDUCE-4229 > Project: Hadoop Map/Reduce > Issue Type: Improvement > Components: jobtracker > Affects Versions: 1.0.2, 3.0.0, 2.0.2-alpha > Reporter: Todd Lipcon > Attachments: MAPREDUCE-4229-branch-0.23.patch, MAPREDUCE-4229.patch > > > In our experience, most of the memory in production JTs goes to storing > counter names (String objects and character arrays). Since most counter names > are reused again and again, it would be a big memory savings to keep a hash > set of already-used counter names within a job, and refer to the same object > from all tasks. -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators For more information on JIRA, see: http://www.atlassian.com/software/jira