New submission from Richard Oudkerk <shibt...@gmail.com>: Multiprocessing's process pool originally used a finalizer to shutdown the pool when the pool object is garbage collected.
Since the maxtasksperchild feature was added, the worker_handler thread holds a reference to the pool, preventing garbage collection at least until that thread finished. In some cases the last reference to the pool is owned by the worker_handler thread, and as it exits, the finalizer is triggered. Since the finalizer tries to join the worker_handler thread, an error will be raised since a thread cannot join itself. It would have been better if pools had used the context manager protocol rather than using RAII -- see Issue #15064. Unless/until RAII usage is fixed, a quick fix would be to just make the finalizer skip trying to join the current thread. ---------- messages: 163101 nosy: sbt priority: normal severity: normal status: open title: multiprocessing pool finalizer can fail if triggered in background pool thread type: behavior _______________________________________ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue15101> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
