New submission from Michael Hall <michaelhal...@gmail.com>: I recently switched to Ubuntu 11.04 from OpenSUSE 11.4, and when I go to run a project I coded a couple days ago under OpenSUSE using the multiprocessing library, it hangs when it did not under OpenSUSE.
Specifically, I am using two queues, work_queue from which the children get jobs, and results_queue where they place their results before calling JoinableQueue.task_done() and grabbing the next result. I use the "poison pill" technique to terminate the children, where a None object is placed at the end of the queue for each child, and when they get one of the terminating objects they call task_done() again (to account for the None object) and exit. In the main process, after spawning all of the children (one per physical CPU), it joins with the work_queue in order to wait for all of its children to finish. This is pretty much a cookie-cutter multiprocessing implementation that I've used successfully for years under OpenSUSE, but for some odd reason the exact same code does not work under Ubuntu. I would try porting to python 3.x, but the rest of my research team is still using 2.7, so that's not really an option right now. ---------- components: Library (Lib) messages: 141932 nosy: Michael.Hall priority: normal severity: normal status: open title: Bug in multiprocessing.JoinableQueue() implementation on Ubuntu 11.04 versions: Python 2.7 _______________________________________ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue12738> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
