hadoop-hive-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Namit Jain (JIRA)" <j...@apache.org>
Subject [jira] Commented: (HIVE-1110) add counters to show that skew join triggered
Date Thu, 28 Jan 2010 17:43:34 GMT

    [ https://issues.apache.org/jira/browse/HIVE-1110?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12805999#action_12805999

Namit Jain commented on HIVE-1110:

I am not sure about the semantics of counters - why do you need a bitvector for keeping track
of which one got updated.
Isnt a non-zero value good enough ?

Is the assumption that only 1 reducer will update a particular tag. Even then you will only
be able to know the number
of skew joins - in that case, why do you need to tag array - just increment the counter every
time you see a new key.
Even if you update it multiple times, it is OK.

> add counters to show that skew join triggered
> ---------------------------------------------
>                 Key: HIVE-1110
>                 URL: https://issues.apache.org/jira/browse/HIVE-1110
>             Project: Hadoop Hive
>          Issue Type: Improvement
>          Components: Query Processor
>            Reporter: Namit Jain
>            Assignee: He Yongqiang
>             Fix For: 0.6.0
>         Attachments: hive-1110.patch
> It would be very useful to debug, and quickly find out if the skew join was triggered.

This message is automatically generated by JIRA.
You can reply to this email to add a comment to the issue online.

View raw message