hadoop-common-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Amar Kamat (JIRA)" <j...@apache.org>
Subject [jira] Commented: (HADOOP-5338) Reduce tasks are stuck waiting for map outputs when none are in progress
Date Mon, 02 Mar 2009 08:24:12 GMT

    [ https://issues.apache.org/jira/browse/HADOOP-5338?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12677918#action_12677918
] 

Amar Kamat commented on HADOOP-5338:
------------------------------------

Looks like the problem lies with the _SYNC_ information passed by the job-tracker to the task-tracker.
Upon restart, the job-tracker passes the size of task completion events that the jobtracker
has rebuilt. Events at job-tracker's comprises of all the tasks (map/reduce/cleanup/setup)
while the one at the tracker comprises of just the map tasks. Will upload a patch soon.

> Reduce tasks are stuck waiting for map outputs when none are in progress
> ------------------------------------------------------------------------
>
>                 Key: HADOOP-5338
>                 URL: https://issues.apache.org/jira/browse/HADOOP-5338
>             Project: Hadoop Core
>          Issue Type: Bug
>          Components: mapred
>    Affects Versions: 0.20.0
>            Reporter: Ramya R
>            Assignee: Amar Kamat
>             Fix For: 0.20.0
>
>         Attachments: log.txt
>
>
> When JT is restarted several times, a situation is encountered when the reduce tasks
are stuck forever waiting for map outputs. However 100%map is complete and none of the map
tasks are in progress. The reduce tasks wait infinitely.

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


Mime
View raw message