You are viewing a plain text version of this content. The canonical link for it is here.
Posted to common-dev@hadoop.apache.org by "Alejandro Abdelnur (JIRA)" <ji...@apache.org> on 2008/09/08 05:28:44 UTC

[jira] Updated: (HADOOP-3702) add support for chaining Maps in a single Map and after a Reduce [M*/RM*]

     [ https://issues.apache.org/jira/browse/HADOOP-3702?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Alejandro Abdelnur updated HADOOP-3702:
---------------------------------------

    Status: Open  (was: Patch Available)

> add support for chaining Maps in a single Map and after a Reduce [M*/RM*]
> -------------------------------------------------------------------------
>
>                 Key: HADOOP-3702
>                 URL: https://issues.apache.org/jira/browse/HADOOP-3702
>             Project: Hadoop Core
>          Issue Type: New Feature
>          Components: mapred
>         Environment: all
>            Reporter: Alejandro Abdelnur
>            Assignee: Alejandro Abdelnur
>             Fix For: 0.19.0
>
>         Attachments: Hadoop-3702.patch, patch3702.txt, patch3702.txt, patch3702.txt, patch3702.txt, patch3702.txt, patch3702.txt, patch3702.txt, patch3702.txt, patch3702.txt, patch3702.txt, patch3702.txt, patch3702.txt
>
>
> On the same input, we usually need to run multiple Maps one after the other without no Reduce. We also have to run multiple Maps after the Reduce.
> If all pre-Reduce Maps are chained together and run as a single Map a significant amount of Disk I/O will be avoided. 
> Similarly all post-Reduce Maps can be chained together and run in the Reduce phase after the Reduce.

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