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https://issues.apache.org/jira/browse/MAPREDUCE-2374?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13420970#comment-13420970
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Colin Patrick McCabe commented on MAPREDUCE-2374:
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Ah, you're absolutely right. Without the -c, bash won't execve the file
itself. It will read the file into an already running interpreter. So no
ETXTBSY.
I'm a little nervous about this proposed "fix" because it doesn't really seem
to fix the problem. Are we absolutely sure that the file is closed and not
still being written to? If it's not, we could be getting file descriptor
leaks, partially written scripts, and all the usual evils.
I guess Shrinivas did some testing with lsof. Shrinivas, can you try
deliberately keeping the file open for write and verifying that your lsof test
detects it? Also, it would be interesting to see if the same problem shows up
when using the raw FileChannel API (as opposed to the FileWriter API).
If this is a real kernel bug, I guess we need to file it upstream on the red
hat bug tracker and/or kernel mailing list.
> Should not use PrintWriter to write taskjvm.sh
> ----------------------------------------------
>
> Key: MAPREDUCE-2374
> URL: https://issues.apache.org/jira/browse/MAPREDUCE-2374
> Project: Hadoop Map/Reduce
> Issue Type: Bug
> Affects Versions: 0.22.0
> Reporter: Todd Lipcon
> Assignee: Todd Lipcon
> Fix For: 0.22.1
>
> Attachments: mapreduce-2374-on-20sec.txt, mapreduce-2374.txt,
> mapreduce-2374.txt
>
>
> Our use of PrintWriter in TaskController.writeCommand is unsafe, since that
> class swallows all IO exceptions. We're not currently checking for errors,
> which I'm seeing result in occasional task failures with the message "Text
> file busy" - assumedly because the close() call is failing silently for some
> reason.
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