This might help shed more light on the problem. 1. https://pypi.org/project/pytest-django-queries/ 2. Try cProfile https://www.geeksforgeeks.org/profiling-in-python/
Regards, Chetan Ganji +91-900-483-4183 ganji.che...@gmail.com http://ryucoder.in On Tue, Jun 8, 2021 at 1:33 AM Rich Rauenzahn <rraue...@gmail.com> wrote: > This is heads up in case anyone sees something similar: > > I have managed to trigger this degenerate query case in two completely > different Django 2.2 projects. In production with a normal sized dataset, > the query time is fine. But during unit testing with a small subset of the > data, the queries took a long time. A LONG time. > > In the most recent case each query took 100x longer. 200+ seconds instead > of 2 seconds. The unit test dataset isn't very large because it's a unit > test. > > I think I may have first seen this when I upgraded the project to postgres > 11. > > Manually vacuuming between tests resolves the issue. (Yes, autovacuum is > on by default -- and isn't the db created from scratch for each 'manage > test' invocation?) > > This is how I did it: > > def _vacuum(): > # Some unit test queries seem to take a much longer time. > # Let's try vacuuming. > # https://stackoverflow.com/a/13955271/2077386 > with connection.cursor() as cursor: > logger.info("Vacuum: begin") > cursor.execute("VACUUM ANALYZE") > logger.info("Vacuum: complete") > > class VacuumMixin: > @classmethod > def setUpClass(cls): > _vacuum() > return super().setUpClass() > > @classmethod > def tearDownClass(cls): > ret = super().tearDownClass() > _vacuum() > return ret > > If anyone else sees this, please let me know. Maybe we can further RCA it. > > > > -- > You received this message because you are subscribed to the Google Groups > "Django users" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to django-users+unsubscr...@googlegroups.com. > To view this discussion on the web visit > https://groups.google.com/d/msgid/django-users/e76b105e-ed53-4031-869c-830f94677ef4n%40googlegroups.com > <https://groups.google.com/d/msgid/django-users/e76b105e-ed53-4031-869c-830f94677ef4n%40googlegroups.com?utm_medium=email&utm_source=footer> > . > -- You received this message because you are subscribed to the Google Groups "Django users" group. To unsubscribe from this group and stop receiving emails from it, send an email to django-users+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/django-users/CAMKMUjuJPTLxOUF0x5knQOtpCUy0V3tuV2QkwFMH5yVGoym1sw%40mail.gmail.com.
