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https://issues.apache.org/jira/browse/MAPREDUCE-1608?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12932566#action_12932566
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Arun C Murthy commented on MAPREDUCE-1608:
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How do you prevent devious/malicious users from speculating on all their tasks 
via a simple shell script?

> Allow users to do speculative execution of a task manually
> ----------------------------------------------------------
>
>                 Key: MAPREDUCE-1608
>                 URL: https://issues.apache.org/jira/browse/MAPREDUCE-1608
>             Project: Hadoop Map/Reduce
>          Issue Type: New Feature
>            Reporter: Scott Chen
>            Assignee: Scott Chen
>
> Speculative execution improves the latency of the job. Sometimes the job has 
> few very slow reducers. Spending a little more resource on speculative tasks 
> can improve the latency a lot. It will be nice that the users can manually 
> select one task and force the speculative execution on that task just like we 
> can manually kill/fail task.
> The proposal is add link says "speculate" in taskdetails.jsp page where we do 
> "kill/fail".
> Thoughts? 

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