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Author giampaolo.rodola
Recipients davin, giampaolo.rodola, pitrou
Date 2019-02-06.17:36:20
SpamBayes Score -1.0
Marked as misclassified Yes
Message-id <>
import multiprocessing
import multiprocessing.managers

def f(n):
    return n * n

def worker(pool):
    with pool:
        pool.apply_async(f, (10, ))

manager = multiprocessing.managers.SyncManager()
pool = manager.Pool(processes=4)
proc = multiprocessing.Process(target=worker, args=(pool, ))

This is related to BPO-35917 and it fails with:

Process Process-2:
Traceback (most recent call last):
  File "/home/giampaolo/cpython/Lib/multiprocessing/", line 302, in _bootstrap
  File "/home/giampaolo/cpython/Lib/multiprocessing/", line 99, in run
    self._target(*self._args, **self._kwargs)
  File "", line 54, in worker
    pool.apply_async(f, (10, ))
  File "<string>", line 2, in apply_async
  File "/home/giampaolo/cpython/Lib/multiprocessing/", line 802, in _callmethod
    proxytype = self._manager._registry[token.typeid][-1]
AttributeError: 'NoneType' object has no attribute '_registry'
Date User Action Args
2019-02-06 17:36:22giampaolo.rodolasetrecipients: + giampaolo.rodola, pitrou, davin
2019-02-06 17:36:20giampaolo.rodolasetmessageid: <>
2019-02-06 17:36:20giampaolo.rodolalinkissue35919 messages
2019-02-06 17:36:20giampaolo.rodolacreate