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https://issues.apache.org/jira/browse/HIVE-17783?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16202623#comment-16202623
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Sergey Shelukhin commented on HIVE-17783:
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Hmm, we observed this with LLAP (which has advantage of table sharing in
non-hybrid case), but not with containers to the best of my knowledge. It's
possible it's slower even w/o accounting for sharing.
It's also possible that mapjoin table size was configured to be too small so
there was too much needless spilling...
[~gopalv] any input?
We could disable it by default if it's hard to tune. Then for the cases where
it can shine people can turn it on and tune the sizing.
> Hybrid Grace Hash Join has performance degradation for N-way join using Hive
> on Tez
> -----------------------------------------------------------------------------------
>
> Key: HIVE-17783
> URL: https://issues.apache.org/jira/browse/HIVE-17783
> Project: Hive
> Issue Type: Bug
> Affects Versions: 2.2.0
> Environment: 8*Intel(R) Xeon(R) CPU E5-2699 v4 @ 2.20GHz
> 1 master + 7 workers
> TPC-DS at 3TB data scales
> Hive version : 2.2.0
> Reporter: Ferdinand Xu
> Attachments: Hybrid_Grace_Hash_Join.xlsx
>
>
> Most configurations are using default value. And the benchmark is to test
> enabling against disabling hybrid grace hash join using TPC-DS queries at 3TB
> data scales. Many queries related to N-way join has performance degradation
> over three times test. Detailed result is attached.
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