Noe Brucy
64 lines
1.5 KiB
Python
64 lines
1.5 KiB
Python
#!/usr/bin/env python
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# -*- coding: utf-8 -*-
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import multiprocessing
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# We must import this explicitly, it is not imported by the top-level
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# multiprocessing module.
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import multiprocessing.pool
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import time
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from random import randint
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class NoDaemonProcess(multiprocessing.Process):
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# make 'daemon' attribute always return False
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def _get_daemon(self):
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return False
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def _set_daemon(self, value):
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pass
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daemon = property(_get_daemon, _set_daemon)
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# We sub-class multiprocessing.pool.Pool instead of multiprocessing.Pool
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# because the latter is only a wrapper function, not a proper class.
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class MyPool(multiprocessing.pool.Pool):
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Process = NoDaemonProcess
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def sleepawhile(t):
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print("Sleeping %i seconds..." % t)
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time.sleep(t)
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return t
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def work(num_procs):
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print("Creating %i (daemon) workers and jobs in child." % num_procs)
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pool = multiprocessing.Pool(num_procs)
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result = pool.map(sleepawhile, [randint(1, 5) for x in range(num_procs)])
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# The following is not really needed, since the (daemon) workers of the
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# child's pool are killed when the child is terminated, but it's good
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# practice to cleanup after ourselves anyway.
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pool.close()
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pool.join()
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return result
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def test():
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print("Creating 5 (non-daemon) workers and jobs in main process.")
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pool = MyPool(5)
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result = pool.map(work, [randint(1, 5) for x in range(5)])
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pool.close()
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pool.join()
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print(result)
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if __name__ == "__main__":
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test()
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