hadoop-mapreduce-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Jagane Sundar (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (MAPREDUCE-2413) TaskTracker should handle disk failures at both startup and runtime
Date Wed, 20 Apr 2011 00:16:06 GMT

    [ https://issues.apache.org/jira/browse/MAPREDUCE-2413?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13021871#comment-13021871
] 

Jagane Sundar commented on MAPREDUCE-2413:
------------------------------------------

Owen - I have made the comment change that you suggested, and uploaded MR-2413.v0.2.patch.
Please review and accept.

> TaskTracker should handle disk failures at both startup and runtime
> -------------------------------------------------------------------
>
>                 Key: MAPREDUCE-2413
>                 URL: https://issues.apache.org/jira/browse/MAPREDUCE-2413
>             Project: Hadoop Map/Reduce
>          Issue Type: Improvement
>          Components: task-controller, tasktracker
>    Affects Versions: 0.20.204.0
>            Reporter: Bharath Mundlapudi
>            Assignee: Ravi Gummadi
>             Fix For: 0.20.204.0
>
>         Attachments: MR-2413.v0.1.patch, MR-2413.v0.2.patch, MR-2413.v0.patch
>
>
> At present, TaskTracker doesn't handle disk failures properly both at startup and runtime.
> (1) Currently TaskTracker doesn't come up if any of the mapred-local-dirs is on a bad
disk. TaskTracker should ignore that particular mapred-local-dir and start up and use only
the remaining good mapred-local-dirs.
> (2) If a disk goes bad while TaskTracker is running, currently TaskTracker doesn't do
anything special. This results in either
>    (a) TaskTracker continues to "try to use that bad disk" and this results in lots of
task failures and possibly job failures(because of multiple TTs having bad disks) and eventually
these TTs getting graylisted for all jobs. And this needs manual restart of TT with modified
configuration of mapred-local-dirs avoiding the bad disk. OR
>    (b) Health check script identifying the disk as bad and the TT gets blacklisted. And
this also needs manual restart of TT with modified configuration of mapred-local-dirs avoiding
the bad disk.
> This JIRA is to make TaskTracker more fault-tolerant to disk failures solving (1) and
(2). i.e. TT should start even if at least one of the mapred-local-dirs is on a good disk
and TT should adjust its in-memory list of mapred-local-dirs and avoid using bad mapred-local-dirs.

--
This message is automatically generated by JIRA.
For more information on JIRA, see: http://www.atlassian.com/software/jira

Mime
View raw message