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Scott Chen commented on MAPREDUCE-1463: --------------------------------------- @Todd: That is a good point. If the reducer can later on catch up with the mapper, then there is no harm for the delay at the beginning. @Arun: I know you don't like this because it increases the complexity. Will you feel more comfortable if we move this just inside fairscheduler? > Reducer should start faster for smaller jobs > -------------------------------------------- > > Key: MAPREDUCE-1463 > URL: https://issues.apache.org/jira/browse/MAPREDUCE-1463 > Project: Hadoop Map/Reduce > Issue Type: Improvement > Components: jobtracker > Reporter: Scott Chen > Assignee: Scott Chen > Attachments: MAPREDUCE-1463-v1.patch, MAPREDUCE-1463-v2.patch, > MAPREDUCE-1463-v3.patch > > > Our users often complain about the slowness of smaller ad-hoc jobs. > The overhead to wait for the reducers to start in this case is significant. > It will be good if we can start the reducer sooner in this case. -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online.