New submission from Greg Brockman <g...@ksplice.com>: I have recently begun using multiprocessing for a variety of batch jobs. It's a great library, and it's been quite useful. However, I have been bitten several times by situations where a worker process in a Pool will unexpectedly die, leaving multiprocessing hanging in a wait. A simple example of this is produced by the following: """ #!/usr/bin/env python import multiprocessing, sys def foo(x): sys.exit(1) multiprocessing.Pool(1).apply(foo, [1]) """ The child will exit and the parent will hang forever. A similar occurrence happens if one pushes C-c while a child process is running (this special case is noted in http://bugs.python.org/issue8296) or killed by a signal.
Attached is a patch to handle unexpected terminations of children processes and prevent the parent process from hanging. A test case is included. (Developed and tested on 64-bit Ubuntu.) Please let me know what you think. Thanks! ---------- components: Library (Lib) files: termination.patch keywords: patch messages: 109585 nosy: gdb priority: normal severity: normal status: open title: Parent process hanging in multiprocessing if children terminate unexpectedly type: behavior versions: Python 2.6, Python 2.7 Added file: http://bugs.python.org/file17905/termination.patch _______________________________________ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue9205> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
