You are viewing a plain text version of this content. The canonical link for it is here.

Posted to mapreduce-issues@hadoop.apache.org by "Allen Wittenauer (JIRA)" <ji...@apache.org> on 2014/07/21 22:04:41 UTC

[jira] [Resolved] (MAPREDUCE-192) In TaskTracker, the notification for waking up the completion-events fetcher thread may be lost

     [ https://issues.apache.org/jira/browse/MAPREDUCE-192?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Allen Wittenauer resolved MAPREDUCE-192.
----------------------------------------

    Resolution: Incomplete

I'm.... just gonna close this as stale.

> In TaskTracker, the notification for waking up the completion-events fetcher thread may be lost
> -----------------------------------------------------------------------------------------------
>
>                 Key: MAPREDUCE-192
>                 URL: https://issues.apache.org/jira/browse/MAPREDUCE-192
>             Project: Hadoop Map/Reduce
>          Issue Type: Bug
>            Reporter: Devaraj Das
>            Assignee: Devaraj Das
>         Attachments: 5245.patch
>
>
> In the TaskTracker, there is a completion events fetcher thread that fetches new events from the JobTracker. Normally, the fetcher thread would sleep for heartbeatInterval amount of time per cycle. When a reduce task asks for completion events from the corresponding TaskTracker and the TaskTracker currently doesn't have anything to hand out, a notification is sent to the completion events fetcher thread to wake up and fetch new events if any. Sometimes this notification could be lost and the reduce task would be idle for a few seconds. This hurts the performance of jobs like terasort.



--
This message was sent by Atlassian JIRA
(v6.2#6252)