hadoop-mapreduce-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Robert Joseph Evans (JIRA)" <j...@apache.org>
Subject [jira] [Resolved] (MAPREDUCE-5051) Combiner not used when NUM_REDUCES=0
Date Thu, 07 Mar 2013 19:20:13 GMT

     [ https://issues.apache.org/jira/browse/MAPREDUCE-5051?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel

Robert Joseph Evans resolved MAPREDUCE-5051.

    Resolution: Won't Fix

If you feel strongly that this should be supported you can reopen this JIRA as new feature
> Combiner not used when NUM_REDUCES=0
> ------------------------------------
>                 Key: MAPREDUCE-5051
>                 URL: https://issues.apache.org/jira/browse/MAPREDUCE-5051
>             Project: Hadoop Map/Reduce
>          Issue Type: Bug
>          Components: mrv1
>    Affects Versions: 2.0.2-alpha
>         Environment: CDH4.1.2 MR1
>            Reporter: Damien Hardy
> We have a M/R job that use Mapper + Combiner but have nothing to do in Reducer :
> Bulk indexing of HBase data in ElasticSearch,
> Map output is K / V : #bulk / json_data_to_be_indexed.
> So job is launched maps work, combiners index and a reducer is created for nothing (sometimes
waiting for other M/R job to free a tasktracker slot for reducer cf. MAPREDUCE-5019 )
> When we put ```job.setNumReduceTasks(0);``` in our job .run(), mapper are started but
combiner are not used.

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

View raw message