hadoop-pig-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Olga Natkovich (JIRA)" <j...@apache.org>
Subject [jira] Updated: (PIG-196) Pig should use '-reducer NONE' for map-only jobs
Date Tue, 30 Sep 2008 23:07:44 GMT

     [ https://issues.apache.org/jira/browse/PIG-196?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]

Olga Natkovich updated PIG-196:
-------------------------------

    Resolution: Fixed
        Status: Resolved  (was: Patch Available)

This issue is resolved on the types branch

> Pig should use '-reducer NONE' for map-only jobs
> ------------------------------------------------
>
>                 Key: PIG-196
>                 URL: https://issues.apache.org/jira/browse/PIG-196
>             Project: Pig
>          Issue Type: Bug
>            Reporter: Arun C Murthy
>            Assignee: Arun C Murthy
>         Attachments: PIG-196_0_20080412.patch, PIG-196_1_20080422.patch
>
>
> Currently, for map-only jobs, Pig writes map-outputs directly to HDFS and then sends
zero data to reducers. The problem with this is two fold:
>  * Reduce slots are unnecessarily wasted on the cluster
>  * Reduces write empty files to HDFS putting pressure on the Namenode
> Both these can we very easily avoided by just calling:
> {noformat}
> job.setNumReduces(0);
> {noformat}
> and letting Hadoop Map-Reduce take care of writing map-outputs directly to HDFS.

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


Mime
View raw message