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Alan Gates commented on PIG-480: -------------------------------- What kind of performance gain do we get from this? The only PigMIx query that looks like it would be directly affected is PigMix_3. It would be interesting to run that and a few other queries that we expect would benefit from this to measure the performance improvements. > PERFORMANCE: Use identity mapper in a chain of M-R jobs > ------------------------------------------------------- > > Key: PIG-480 > URL: https://issues.apache.org/jira/browse/PIG-480 > Project: Pig > Issue Type: Improvement > Affects Versions: 0.2.0 > Reporter: Olga Natkovich > Assignee: Ying He > Attachments: PIG_480.patch, PIG_480.patch > > > For jobs with two or more MR jobs, use identity mapper wherever possible in > second and subsequent MR jobs. Identity mapper is about 50% than pig empty > map job because it doesn't parse the data. -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online.