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Vinod Kumar Vavilapalli updated MAPREDUCE-3805: ----------------------------------------------- Attachment: MAPREDUCE-3805-20120203.txt A very raw patch that we were using for GridMix with high ram reduces. This needs cleanup and tests. > MR AM not respecting MaxReduceRampUpLimit > ----------------------------------------- > > Key: MAPREDUCE-3805 > URL: https://issues.apache.org/jira/browse/MAPREDUCE-3805 > Project: Hadoop Map/Reduce > Issue Type: Bug > Components: mr-am, mrv2 > Affects Versions: 0.23.0 > Reporter: Vinod Kumar Vavilapalli > Assignee: Vinod Kumar Vavilapalli > Fix For: 0.23.1 > > Attachments: MAPREDUCE-3805-20120203.txt > > > While running GridMixV3 with high memory reduces, we ran into issues where > for jobs with significant number of maps and reduces, when the map progress > hits 98-99% but still there are maps pending, reduces get every new container > that RM allocates. And the job takes much longer time than with usual reduces. > For addressing precisely these issues, a configurable limit was introduced to > limit the reduce ramp up. Unfortunately this limit is not working correctly. -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators: https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa For more information on JIRA, see: http://www.atlassian.com/software/jira