I'm also seeing the incref error occasionally, on OS X 10.5.4:
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ERROR: test_remote (__main__.WithManagerTestRemoteManager)
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Traceback (most recent call last):
File "Lib/test/test_multiprocessing.py", line 1157, in test_remote
queue = manager2.get_queue()
File "/Users/dickinsm/python_source/trunk/Lib/multiprocessing/managers.py", line 635, in temp
authkey=self._authkey, exposed=exp
File "/Users/dickinsm/python_source/trunk/Lib/multiprocessing/managers.py", line 887, in AutoProxy
incref=incref)
File "/Users/dickinsm/python_source/trunk/Lib/multiprocessing/managers.py", line 696, in __init__
self._incref()
File "/Users/dickinsm/python_source/trunk/Lib/multiprocessing/managers.py", line 743, in _incref
dispatch(conn, None, 'incref', (self._id,))
File "/Users/dickinsm/python_source/trunk/Lib/multiprocessing/managers.py", line 79, in dispatch
raise convert_to_error(kind, result)
RemoteError:
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Traceback (most recent call last):
File "/Users/dickinsm/python_source/trunk/Lib/multiprocessing/managers.py", line 181, in handle_request
result = func(c, *args, **kwds)
File "/Users/dickinsm/python_source/trunk/Lib/multiprocessing/managers.py", line 397, in incref
self.id_to_refcount[ident] += 1
KeyError: '6fdb78'
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