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https://issues.apache.org/jira/browse/HADOOP-10146?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13852505#comment-13852505
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Vinod Kumar Vavilapalli commented on HADOOP-10146:
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Yeah, +1 barring that point about code comment.

> Workaround JDK7 Process fd close bug
> ------------------------------------
>
>                 Key: HADOOP-10146
>                 URL: https://issues.apache.org/jira/browse/HADOOP-10146
>             Project: Hadoop Common
>          Issue Type: Bug
>          Components: util
>    Affects Versions: 0.23.0, 2.0.0-alpha, 3.0.0
>            Reporter: Daryn Sharp
>            Assignee: Daryn Sharp
>            Priority: Critical
>         Attachments: HADOOP-10129.branch-23.patch, HADOOP-10129.patch
>
>
> JDK7's {{Process}} output streams have an async fd-close race bug.  This 
> manifests as commands run via o.a.h.u.Shell causing threads to hang, OOM, or 
> cause other bizarre behavior.  The NM is likely to encounter the bug under 
> heavy load.
> Specifically, {{ProcessBuilder}}'s {{UNIXProcess}} starts a thread to reap 
> the process and drain stdout/stderr to avoid a lingering zombie process.  A 
> race occurs if the thread using the stream closes it, the underlying fd is 
> recycled/reopened, while the reaper is draining it.  
> {{ProcessPipeInputStream.drainInputStream}}'s will OOM allocating an array if 
> {{in.available()}} returns a huge number, or may wreak havoc by incorrectly 
> draining the fd.



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