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https://issues.apache.org/jira/browse/MAPREDUCE-5387?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13708079#comment-13708079
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Ivan Mitic commented on MAPREDUCE-5387:
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Copy-pasting [~cnauroth] comment from MAPREDUCE-5330:
{quote}
I came across similar issues while working on the YARN nodemanager changes for
Windows. Bikas, I agree that this logic doesn't exactly match the meaning of
SIGTERM. To match SIGTERM, we really need a way for one process to signal
another process with some "graceful shutdown" message, and a way for the other
process to trigger custom code when it receives that message. Unfortunately,
I'm not aware of anything in the Windows API that provides an exact match.
Therefore, the logic in this patch seems to be the closest approximation that's
feasible right now.
To elaborate on this, TerminateProcess immediately kills the target process,
and there is no way for that process to trap the call and run custom clean-up
code.
http://msdn.microsoft.com/en-us/library/windows/desktop/ms686714(v=vs.85).aspx
This is much different from Unix signals, which allow the target process to
install signal handlers to respond gracefully to things like SIGTERM.
There also seems to be some support for programmatically sending CTL-C to a
process and installing a custom handler to respond to it. This would be
SetConsoleCtrlHandler and GenerateConsoleCtrlEvent. I've heard anecdotally that
this can be used to create a rough approximation of Unix signals, but I haven't
tried it myself.
http://msdn.microsoft.com/en-us/library/windows/desktop/ms686016(v=vs.85).aspx
http://msdn.microsoft.com/en-us/library/windows/desktop/ms683155(v=vs.85).aspx
Aside from that, the only other option seems to be for Windows applications to
roll their own custom IPC protocol (i.e. one process sends another a custom
graceful shutdown message over a named pipe).
It might be worth pursuing one of these solutions in the long term for absolute
correctness, but these approaches will require a lot more coding and testing.
{quote}
> Implement Signal.TERM on Windows
> --------------------------------
>
> Key: MAPREDUCE-5387
> URL: https://issues.apache.org/jira/browse/MAPREDUCE-5387
> Project: Hadoop Map/Reduce
> Issue Type: Bug
> Affects Versions: 3.0.0, 1-win, 2.1.0-beta
> Reporter: Ivan Mitic
> Assignee: Ivan Mitic
>
> Signal.TERM is currently not supported by Hadoop on the Windows platform.
> Tracking Jira for the problem.
> A couple of things to keep in mind:
> - Support for process groups (JobObjects on Windows)
> - Solution should work for both java and other streaming Hadoop apps
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