Session-Scoped Fixtures are not Session-Scoped with Pytest-Xdist

I am fairly new to this project. I very recently migrated a software project test-suite from nosetest to pytest, mainly because of the Xdist benefits I had heard of.

The problem is that my Tests are depending on a big fixture setup (table creation + heavy loading of data) that I would like to share across all my tests.

The current Xdist behaviour is as follow:

1. Collect test
2. Split tests amongst the user-defined number of processes
3. Launch a pytest session for each worker

Obviously, if each test depend on a heavy fixture, then multiplying the number of creation per number of worker is not going to help.

Additionally, it simply breaks the expected pytest behaviour for 'session' scoped fixtures.

I think this should be fairly simple to address this problem although I didn't take a really deep look into it. If you need help to solve this problem, I am more than willing to contribute if you feel this suggestion for improvement is relevant.

Greetings.

The issue names no source files, tests, or entry points. Start by reading pytest-xdist's worker/session setup and existing fixture-related tests, then determine how session-scoped fixtures should behave across workers. Done means the intended sharing behavior is defined and covered by tests without breaking distributed execution.