On 30 January 2018 at 02:39, Victor Stinner <victor.stin...@gmail.com> wrote: >> * "-j1" would explicitly turn off multiprocessing > > Running tests "sequentially" but run them in one subprocess per test > file is interesting for tests isolation. Runing tests one by one > reduces the risk of triggering a race condition (test only failing > when the system load is high). > > -jN was always documented as "use multiprocessing". > > Maybe we need a new option to explicitly disable multiprocessing instead? > > vstinner@apu$ ./python -m test > Run tests sequentially > > vs > > vstinner@apu$ ./python -m test -j1 > Run tests in parallel using 1 child processes
Hmm, that's a good point. Maybe a less intrusive alternative would be akin to what we did with the configure script for non-optimised builds: when we display the total duration at the end, append a note in the serial execution case. Something like: Total duration: 16 minutes 33 seconds (serial execution, pass '-j0' for parallel execution) Such a change would be a safe way to nudge new contributors towards "./python -m test -j0" for faster local testing, without risking backwards compatibility issues with existing test suite invocations in other contexts. Cheers, Nick. -- Nick Coghlan | ncogh...@gmail.com | Brisbane, Australia _______________________________________________ Python-Dev mailing list Python-Dev@python.org https://mail.python.org/mailman/listinfo/python-dev Unsubscribe: https://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com