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https://issues.apache.org/jira/browse/HADOOP-5949?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12715078#action_12715078
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Gautam Kowshik commented on HADOOP-5949:
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To add, the job I was running took 1hrs, 22mins, 13sec to fail even though the 
each map fails immediately, within 2-3 minutes

> JobTracker should give preference to failed tasks over virgin tasks so as to 
> terminate the job ASAP if it is eventually going to fail. 
> ---------------------------------------------------------------------------------------------------------------------------------------
>
>                 Key: HADOOP-5949
>                 URL: https://issues.apache.org/jira/browse/HADOOP-5949
>             Project: Hadoop Core
>          Issue Type: Improvement
>          Components: mapred
>            Reporter: Gautam Kowshik
>            Assignee: Devaraj Das
>
> Case in point... I have 1585 maps and 160 slots (40 nodes). The job is such 
> that all maps fail within 2-3 minutes. The job takes forever to realise that 
> the job is bad. It took 2526 failures for it to reach 4 failed attempts for a 
> task. 
> As I understand, currently the JT prefers a failed task if and only if a task 
> tracker with a split replica for that map came asking for a task. In fact 
> there may not be a single TT at all in the mapred cluster which has a replica 
> for the splits used in this job (pre-0.20). This delays the job failure by a 
> lot and hence degrades cluster utilization as a whole. If i'm on a shared 
> cluster with many jobs waiting on it to fail, it's bad. 
> The JT should prefer a failed task a lot earlier than waiting for a data 
> local TT to come around asking. 

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