hive-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Navis (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (HIVE-2340) optimize orderby followed by a groupby
Date Fri, 01 Feb 2013 01:40:11 GMT

    [ https://issues.apache.org/jira/browse/HIVE-2340?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13568361#comment-13568361
] 

Navis commented on HIVE-2340:
-----------------------------

@Gunther Hagleitner,
This optimization copies configuration of childRS to parentRS, which can lead to performance
problems if childRS is run on single or small number of RSs (bucketing, etc), especially when
parentRS is for JOIN or GBY. Thresholding it by "min.reducer" conf seemed not good enough.
Do you have some better idea?
                
> optimize orderby followed by a groupby
> --------------------------------------
>
>                 Key: HIVE-2340
>                 URL: https://issues.apache.org/jira/browse/HIVE-2340
>             Project: Hive
>          Issue Type: Sub-task
>          Components: Query Processor
>            Reporter: Navis
>            Assignee: Navis
>            Priority: Minor
>              Labels: perfomance
>         Attachments: ASF.LICENSE.NOT.GRANTED--HIVE-2340.D1209.1.patch, ASF.LICENSE.NOT.GRANTED--HIVE-2340.D1209.2.patch,
ASF.LICENSE.NOT.GRANTED--HIVE-2340.D1209.3.patch, ASF.LICENSE.NOT.GRANTED--HIVE-2340.D1209.4.patch,
ASF.LICENSE.NOT.GRANTED--HIVE-2340.D1209.5.patch, HIVE-2340.1.patch.txt, HIVE-2340.D1209.6.patch,
HIVE-2340.D1209.7.patch, HIVE-2340.D1209.8.patch, HIVE-2340.D1209.9.patch, testclidriver.txt
>
>
> Before implementing optimizer for JOIN-GBY, try to implement RS-GBY optimizer(cluster-by
following group-by).

--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira

Mime
View raw message