On 16/07/18 07:39, Gerlando Falauto wrote: > On Monday, July 16, 2018 at 6:56:19 AM UTC+2, dieter wrote: >>> ... >>> Why is the main thread taking up so much CPU? >>> I believe at this point listener.stop() should only be waiting for the >>> helper thread to terminate, which I reckon would be implemented by waiting >>> on a semaphore or something (i.e. iowait i.e. 0% CPU). >> >> Maybe, you look at the source code of "listener.stop"? > > I did, forgot to mention that. Culprit is self._thread.join(). > Which is where it waits for the internal thread to terminate, > which I would've expected to wait on a lock or semaphore (pthread_join()?) > So there's something I'm totally missing here, which has more to do > with queues and threads in general than it has with logging. > Any ideas? >
I have no idea what's really going on there, but a quick look through the source reveals that the actual waiting in Thread.join() is done by sem_wait(). via https://github.com/python/cpython/blob/13ff24582c99dfb439b1af7295b401415e7eb05b/Python/thread_pthread.h#L304 via https://github.com/python/cpython/blob/master/Modules/_threadmodule.c#L45 via https://github.com/python/cpython/blob/master/Modules/_threadmodule.c#L136 via https://github.com/python/cpython/blob/master/Lib/threading.py#L1000 -- https://mail.python.org/mailman/listinfo/python-list
