You are viewing a plain text version of this content. The canonical link for it is here.
Posted to common-dev@hadoop.apache.org by "ZhuGuanyin (JIRA)" <ji...@apache.org> on 2009/03/05 07:37:56 UTC
[jira] Commented: (HADOOP-5407) Sometimes, Reduce tasks hang， State is unassigned
[ https://issues.apache.org/jira/browse/HADOOP-5407?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12679091#action_12679091 ]
ZhuGuanyin commented on HADOOP-5407:
------------------------------------
Today, one map task attempt hang, whose state is unassigned. The following log gives the normal log and the exception log.
Normal Log:
-------------------
2009-03-05 11:48:40,527 INFO mapred.TaskTracker (TaskTracker.java:run(314)) - Received KillTaskAction for task: attempt_200903
032231_0534_m_000785_0
2009-03-05 11:48:40,527 INFO mapred.TaskTracker (TaskTracker.java:purgeTask(1392)) - About to purge task: attempt_200903032231
_0534_m_000785_0
2009-03-05 11:48:40,528 INFO mapred.TaskTracker (TaskTracker.java:addFreeSlot(1625)) - addFreeSlot : current free slots : 1
2009-03-05 11:48:40,537 WARN mapred.TaskTracker (TaskTracker.java:reportTaskFinished(2583)) - Unknown child task finshed: atte
mpt_200903032231_0534_m_000785_0. Ignored.
Exception Log
--------------------------
2009-03-05 11:55:51,600 INFO mapred.TaskTracker (TaskTracker.java:run(314)) - Received KillTaskAction for task: attempt_200903
032231_0541_m_000046_1
2009-03-05 11:55:51,603 INFO mapred.TaskTracker (TaskTracker.java:purgeTask(1392)) - About to purge task: attempt_200903032231
_0541_m_000046_1
2009-03-05 11:55:51,603 INFO mapred.TaskTracker (TaskTracker.java:reportDone(2022)) - Task attempt_200903032231_0541_m_000046_
1 is done.
2009-03-05 11:55:51,604 INFO mapred.TaskTracker (TaskTracker.java:reportDone(2023)) - reported output size for attempt_2009030
32231_0541_m_000046_1 was 0
> Sometimes, Reduce tasks hang， State is unassigned
> -------------------------------------------------
>
> Key: HADOOP-5407
> URL: https://issues.apache.org/jira/browse/HADOOP-5407
> Project: Hadoop Core
> Issue Type: Bug
> Components: mapred
> Affects Versions: 0.19.0
> Reporter: ZhuGuanyin
>
> Hi, all
> When our cluster runs for a long time, some reduce tasks running on some tasktrackers hang. Their states are UNASSIGNED. Then, all reduce tasks on these tasktracker will hang.
> We kill the hang reduce task, then the reduce task attempt is re-scheduled to this tasktracker, the attempt task continues to hang. We fail it, it goes to another tasktracker, it is executed successfully.
> Tasktracker which has hang reduce task will receive new reduce task, but the reduce task continue to hang for ever.
> When we reboot the tasktracker machine, reduce task no longer hangs.
--
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.