[
https://issues.apache.org/jira/browse/HADOOP-1984?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#action_12541817
]
Runping Qi commented on HADOOP-1984:
------------------------------------
Ten minutes waiting interval seems too much.
When the interval reach a few minutes, it does not
need to be doubled for the next try.
If one has to wait for 10+ minutes for a map-output,
it may be better off to re-execute the mapper on other nodes
Re-executing a mapper usually takes less than 10 minutes.
> some reducer stuck at copy phase and progress extremely slowly
> --------------------------------------------------------------
>
> Key: HADOOP-1984
> URL: https://issues.apache.org/jira/browse/HADOOP-1984
> Project: Hadoop
> Issue Type: Bug
> Components: mapred
> Affects Versions: 0.16.0
> Reporter: Runping Qi
> Assignee: Amar Kamat
> Priority: Critical
> Fix For: 0.16.0
>
> Attachments: HADOOP-1984.patch
>
>
> In many cases, some reducers got stuck at copy phase, progressing extremely
> slowly.
> The entire cluster seems doing nothing. This causes a very bad long tails of
> otherwise well tuned map/red jobs.
--
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.
