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Daniel Dai commented on PIG-3557: --------------------------------- 1. You can check requestedParallelism for the tezOperator. This should be doable. 2. We can do a non-sorted scatter-gather, but this depends on TEZ-661, we cannot proceed now 4. We could use combiner and duplicate POLimit in the combiner. Otherwise, plan looks good. > Implement optimizations for LIMIT > --------------------------------- > > Key: PIG-3557 > URL: https://issues.apache.org/jira/browse/PIG-3557 > Project: Pig > Issue Type: Sub-task > Components: tez > Affects Versions: tez-branch > Reporter: Alex Bain > Assignee: Alex Bain > > Implement optimizations for LIMIT when other parts of Pig-on-Tez are more > mature. Some of the optimizations mentioned by Daniel include: > 1. If the previous stage using 1 reduce, no need to add one more vertex > 2. If the limitplan is null (ie, not the "limited order by" case), we might > not need a shuffle edge, a pass through edge should be enough if possible > 3. Similar to PIG-1270, we can push limit to InputHandler > 4. We also need to think through the "limited order by" case once "order by" > is implemented -- This message was sent by Atlassian JIRA (v6.1.5#6160)