[
https://issues.apache.org/jira/browse/MAPREDUCE-5211?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Konstantin Boudnik reopened MAPREDUCE-5211:
-------------------------------------------
This needs to go into the next stabilization release of 2.0.4.2 as well. Adding
the label to that effect and re-opening the ticket.
> Reducer intermediate files can collide during merge
> ---------------------------------------------------
>
> Key: MAPREDUCE-5211
> URL: https://issues.apache.org/jira/browse/MAPREDUCE-5211
> Project: Hadoop Map/Reduce
> Issue Type: Bug
> Components: mrv2
> Affects Versions: 0.23.7
> Reporter: Jason Lowe
> Assignee: Jason Lowe
> Priority: Blocker
> Labels: 2.0.4.2
> Fix For: 0.23.8
>
> Attachments: MAPREDUCE-5211.branch-0.23.patch
>
>
> The OnDiskMerger.merge method constructs an output path that is not unique to
> a reduce attempt, and as a result can result in a file collision with other
> reducers from the same app that are running on the same node. In addition
> the name of the output file is based on MapOutput.toString which may not be
> unique in light of multi-pass merges on disk since the mapId will be null and
> the basename ends up as "MapOutput(null, DISK)"
--
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
