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Jie Li commented on PIG-483: ---------------------------- For the skew join, if the partition table turns out to be small, then we can convert it to a normal join, which doesn't need the sampler either. Would open another jira for that. > PERFORMANCE: different strategies for large and small order bys > --------------------------------------------------------------- > > Key: PIG-483 > URL: https://issues.apache.org/jira/browse/PIG-483 > Project: Pig > Issue Type: Improvement > Affects Versions: 0.2.0 > Reporter: Olga Natkovich > Labels: gsoc2011, performance > > Currently pig always does a multi-pass order by where it first determines a > distribution for the keys and then orders in a second pass. This avoids the > necessity of having a single reducer. However, in cases where the data is > small enough to fit into a single reducer, this is inefficient. For small > data sets it would be good to realize the small size of the set and do the > order by in a single pass with a single reducer. > This is a candidate project for Google summer of code 2011. More information > about the program can be found at http://wiki.apache.org/pig/GSoc2011 -- 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