New submission from Frédéric Sagnes <speedup+pyt...@gmail.com>: Objects contained in a multiprocessing.Queue object are not comming out of the queue in the same order as they went in. For instance, if I put in object1, object2 and object3 in this very time sequence from multiple processes, they can end up comming out of the queue as object2, object1 then object3 instead of the original order.
When using the threading module instead of multiprocessing everything is fine. The provided test script adds strings to the queue with timestamps. These messages are not ordered by timestamp when they are printed. This is an output of the test script with format "[...@time] message": [2...@00406] Got lock [2...@02424] Released lock [2...@02426] Got lock [2...@04439] Released lock [...] [2...@16459] Released lock [2...@16461] Got lock [2...@18464] Got lock [2...@18462] Released lock [2...@20466] Released lock Using print to print the message immediatly prints the messages in the right order. See this mailing-list thread for details: http://groups.google.com/group/comp.lang.python/browse_thread/thread/11a5c4ce4ff4382d/033dcd3607eacbf9 ---------- components: Extension Modules files: testthreads.py messages: 80162 nosy: ndfred severity: normal status: open title: multiprocessing.Queue does not order objects versions: Python 2.6 Added file: http://bugs.python.org/file12793/testthreads.py _______________________________________ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue4999> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
