hadoop-mapreduce-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Alejandro Abdelnur (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (MAPREDUCE-4843) When using DefaultTaskController, JobLocalizer not thread safe
Date Mon, 04 Feb 2013 22:26:14 GMT

    [ https://issues.apache.org/jira/browse/MAPREDUCE-4843?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13570694#comment-13570694
] 

Alejandro Abdelnur commented on MAPREDUCE-4843:
-----------------------------------------------

+1. As per discussion in MAPREDUCE-4964 the latest patch seems a better way of doing it.
                
> When using DefaultTaskController, JobLocalizer not thread safe
> --------------------------------------------------------------
>
>                 Key: MAPREDUCE-4843
>                 URL: https://issues.apache.org/jira/browse/MAPREDUCE-4843
>             Project: Hadoop Map/Reduce
>          Issue Type: Bug
>          Components: tasktracker
>    Affects Versions: 1.1.1
>            Reporter: zhaoyunjiong
>            Assignee: Karthik Kambatla
>            Priority: Critical
>         Attachments: MAPREDUCE-4843-branch-1.1.patch, mr-4843.patch
>
>
> In our cluster, some times job will failed due to below exception:
> 2012-12-03 23:11:54,811 WARN org.apache.hadoop.mapred.TaskTracker: Error initializing
attempt_201212031626_1115_r_000023_0:
> org.apache.hadoop.util.DiskChecker$DiskErrorException: Could not find taskTracker/$username/jobcache/job_201212031626_1115/job.xml
in any of the configured local directories
> 	at org.apache.hadoop.fs.LocalDirAllocator$AllocatorPerContext.getLocalPathToRead(LocalDirAllocator.java:424)
> 	at org.apache.hadoop.fs.LocalDirAllocator.getLocalPathToRead(LocalDirAllocator.java:160)
> 	at org.apache.hadoop.mapred.TaskTracker.initializeJob(TaskTracker.java:1175)
> 	at org.apache.hadoop.mapred.TaskTracker.localizeJob(TaskTracker.java:1058)
> 	at org.apache.hadoop.mapred.TaskTracker.startNewTask(TaskTracker.java:2213)
> The root cause is JobLocalizer is not thread safe.
> In DefaultTaskController.initializeJob method:
>      JobLocalizer localizer = new JobLocalizer((JobConf)getConf(), user, jobid);
> but in JobLocalizer, it just simply keep the reference of the conf.
> When two TaskLauncher threads(mapLauncher and reduceLauncher) try to initializeJob at
same time, it will have two JobLocalizer, but only one conf instance.
> So some times ttConf.setStrings(JOB_LOCAL_CTXT, localDirs) will reset previous job's
conf.
> Then it will cause the previous job's job.xml stored at another user's dir.

--
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

Mime
View raw message