[jira] [Commented] (HIVE-21399) Adjust hive.map.aggr.hash.min.reduction statically depending on group by statistics

["Vineet Garg (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/HIVE-21399?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16786280#comment-16786280 ] 

Vineet Garg commented on HIVE-21399:
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[~jcamachorodriguez] Shouldn't {{SetHashGroupByMinReduction}} be only run for map side aggregation? May be I missed something but I don't see the check.

> Adjust hive.map.aggr.hash.min.reduction statically depending on group by statistics
> -----------------------------------------------------------------------------------
>
>                 Key: HIVE-21399
>                 URL: https://issues.apache.org/jira/browse/HIVE-21399
>             Project: Hive
>          Issue Type: Improvement
>          Components: Hive
>            Reporter: Jesus Camacho Rodriguez
>            Assignee: Jesus Camacho Rodriguez
>            Priority: Major
>         Attachments: HIVE-21399.01.patch
>
>
> Currently, the value is set statically from config variable. If stats are available, we could try to adjust this value at optimization time to favor turning off hash aggregation earlier.



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