Antoine Pitrou <pit...@free.fr> added the comment: > It appears to be better to use clock_gettime(CLOCK_MONOTONIC) > where available and only use gettimeofday() as fallback solution > together with times(), ftime() and time().
Ok, I've tried and it's less good than expected. Using CLOCK_MONOTONIC absolutely kills efficiency. CLOCK_REALTIME is ok but it has no obvious benefits (microsecond resolution as given by gettimeofday() is probably sufficient). The explanation AFAICT is that pthread_cond_timedwait() waits for absolute clock values as given by CLOCK_REALTIME. CLOCK_MONOTONIC gives other values (the man page says: "represents monotonic time since some unspecified starting point"). These values are probably "in the past" as seen from pthread_cond_timedwait(), which implies a busy loop of waiting for the GIL to be released, inside of being suspended gracefully until the timeout. I can still produce a patch with only CLOCK_REALTIME but I'm not sure it's worth the code complication. ---------- _______________________________________ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue7753> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
