You are viewing a plain text version of this content. The canonical link for it is here.
Posted to mapreduce-issues@hadoop.apache.org by "Jeff Bean (JIRA)" <ji...@apache.org> on 2011/08/29 19:22:38 UTC
[jira] [Updated] (MAPREDUCE-2905) Allow
mapred.fairscheduler.assignmultple to be set per job
[ https://issues.apache.org/jira/browse/MAPREDUCE-2905?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Jeff Bean updated MAPREDUCE-2905:
---------------------------------
Description:
We encountered a situation where in the same cluster, large jobs benefit from mapred.fairscheduler.assignmultiple, but small jobs with small numbers of mappers do not: the mappers all clump to fully occupy just a few nodes, which causes those nodes to saturate and bottleneck. The desired behavior is to spread the job across more nodes so that a relatively small job doesn't saturate any node in the cluster.
It'd be nice developers can set a param similar to mapred.fairscheduler.assignmultiple on a per-job basis to better control the task allocation of a particular job.
was:
We encountered a situation where in the same cluster, large jobs benefit from mapred.fairscheduler.assignmultiple, but small jobs with small numbers of mappers do not: the mappers all clump to fully occupy just a few nodes, which causes those nodes to saturate and bottleneck. The desired behavior is to round-robin spread the job across more nodes.
It'd be nice developers can set a param similar to mapred.fairscheduler.assignmultiple on a per-job basis to better control the task allocation of a particular job.
> Allow mapred.fairscheduler.assignmultple to be set per job
> ----------------------------------------------------------
>
> Key: MAPREDUCE-2905
> URL: https://issues.apache.org/jira/browse/MAPREDUCE-2905
> Project: Hadoop Map/Reduce
> Issue Type: Improvement
> Components: contrib/fair-share
> Reporter: Jeff Bean
>
> We encountered a situation where in the same cluster, large jobs benefit from mapred.fairscheduler.assignmultiple, but small jobs with small numbers of mappers do not: the mappers all clump to fully occupy just a few nodes, which causes those nodes to saturate and bottleneck. The desired behavior is to spread the job across more nodes so that a relatively small job doesn't saturate any node in the cluster.
> It'd be nice developers can set a param similar to mapred.fairscheduler.assignmultiple on a per-job basis to better control the task allocation of a particular job.
--
This message is automatically generated by JIRA.
For more information on JIRA, see: http://www.atlassian.com/software/jira