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



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