[Python-Dev] Making "-j0" the default setting for the test suite?
On 1/28/2018 11:43 PM, Guido van Rossum wrote:
> So why can't you just run "make test" if that's faster?
Not a standard option on Windows ;-).
> On Sun, Jan 28, 2018 at 8:30 PM, Nick Coghlan <ncoghlan at gmail.com
> <mailto:ncoghlan at gmail.com>> wrote:
> On my current system, "make test" runs in around 3 minutes, while
> "./python -m test" runs in around 16 minutes. And that's with "make
> test" actually running more tests (since it enables several of the
> "-u" options).
> The difference is that "make test" passes "-j0" and hence not only
> uses all the available cores in the machines, but will also run other
> tests while some tests are sleeping.
> How would folks feel about making "-j 0" the default in the test
> suite, and then adjusted the handling of "-j 1" to switch back to the
> current default single process mode?
> My rationale for that is to improve the default edit-test cycle in
> local development, while still providing a way to force single-process
> execution for failure investigation purposes.
I would like this (though I could write a .bat file). I routinely pass
-j14 or so on a 6 core x 2 processes/core machine and get about the same
times. The speedup would be even better but for the last very long
running test. I wish each test file was limited to about 30 seconds, or
even a minute.
Terry Jan Reedy