pytest run tests parallel

Question

I want to run all my pytest tests in parallel instead of sequentially.

my current setup looks like:

class Test1(OtherClass):
    @pytest.mark.parametrize("activity_name", ["activity1", "activity2"])
    @pytest.mark.flaky(reruns=1)
    def test_1(self, activity_name, generate_test_id):
    """
    """

        test_id = generate_random_test_id()
        test_name = sys._getframe().f_code.co_name

        result_triggers = self.proxy(test_name, generate_test_id, test_id, activity_name)

        expected_items = ["response"]
        validate_response("triggers", result_triggers, expected_items)


    @pytest.mark.parametrize("activity_name", ["activity1", "activity2"])
    @pytest.mark.flaky(reruns=1)
    def test_2(self, activity_name, generate_test_id):
    """
    """

        #same idea...

I run my tests using pytest -v -s.

The result is that my tests are running sequentially, which takes a lot of time since some of them wait for responses from remote servers (integration tests).

Is there any way of running pytest in parallel?

Answer 1

You want pytest-xdist. I think Qxf2 explains it quite well: Qxf2 on Pytest-Xdist

Their Linux command-line is slightly too verbose for my tastes though; I use:

pytest -n <NUM>

where <NUM> is the number of parallel workers.

Answer 2

pytest-xdist is a great solution for most cases, but integration tests are special. After sending a request to a remote server, another test can start on a new thread instead of waiting for a response. This is concurrent testing instead of parallel. Concurrency allows many more tests at once with much less memory and processing overhead.

I wrote the pytest-parallel plugin [py3.6+] to enable parallel and concurrent testing. Here's how to run your integration tests concurrently:

pytest --tests-per-worker auto

Answer 3

pytest-xdist didn't work for me, because my tests were waiting 99.9999999% of the time for glue jobs from AWS to finish, and I was using a CodeBuild environment with 2 cores, so I could only run 2 tests at a time.

@kevelend's approach worked for me.