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Nigel Daley commented on HADOOP-968: ------------------------------------ +1. The latest patch passes my nightly suit of benchmarks. I have resubmitted it to the patch process. > Reduce shuffle and merge should be done a child JVM > --------------------------------------------------- > > Key: HADOOP-968 > URL: https://issues.apache.org/jira/browse/HADOOP-968 > Project: Hadoop > Issue Type: Improvement > Components: mapred > Affects Versions: 0.10.1 > Reporter: Owen O'Malley > Assigned To: Devaraj Das > Fix For: 0.13.0 > > Attachments: 968-reindent.patch, 968-with-metrics-fix.patch, > 968.apr06.patch, 968.apr10.patch, 968.apr14.patch, 968.apr14.patch, 968.patch > > > The Reduce's shuffle and initial merge is done in the TaskTracker's JVM. It > would be better to have it run in the Task's child JVM. The advantages are: > 1. The class path and environment would be set up correctly. > 2. User code doesn't need to be loaded into the TaskTracker. > 3. Lower memory usage and contention in the TaskTracker. -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online.