pytest Quick Start Guide

pytest-xdist

This is a very popular plugin and is maintained by the core developers; it allows you to run tests under multiple CPUs, to speed up the test run.

After installing it, simply use the -n command-line flag to use the given number of CPUs to run the tests:

λ pytest -n 4

And that's it! Now, your tests will run across four cores and hopefully speed up the test suite quite a bit, if it is CPU intensive, thought I/O-bound tests won't see much improvement, though. You can also use -n auto to let pytest-xdist automatically figure out the number of CPUs you have available.

Keep in mind that when your tests are running concurrently, and in random order, they must be careful to avoid stepping on each other's toes, for example, reading/writing ...