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I'm dealing with a python-written server that locks up, and stops working, including logging. I wonder if there's a python equivalent to java's "kill -3" signal that at least prints the current stacktrace.

spike
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    `kill -2` sends SIGINT, which at least on Linux seems to translate into a `KeyboardInterrupt` exception. That might cause a stack trace to be dumped somewhere. It depends on the server of course. – Jason Orendorff Jan 29 '10 at 22:36

3 Answers3

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Use the faulthandler module. https://pypi.python.org/pypi/faulthandler/

import faulthandler
faulthandler.register(signal.SIGUSR1)

This works outside of Python's interpreter loop's signal handling at the C level so it will work even when the Python interpreter itself is hung waiting on something else.

See also: http://docs.python.org/dev/library/faulthandler

gps
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import signal, traceback
def quit_handler(signum,frame):
    traceback.print_stack()
signal.signal(signal.SIGQUIT,quit_handler)
John La Rooy
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  • If the server "locks up", it doesn't necessarily get a SIGQUIT signal, I guess. – AndiDog Jan 29 '10 at 21:35
  • @AndiDog: I think you're supposed to use `kill(1)` to send it one when you manually detect that it has locked up. – SamB Nov 21 '10 at 18:24
0

You can find a (Unix-only) solution in this question.

Community
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AndiDog
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