pytest-flake8 is very slow and uses lots of RAM with -vv
If you run py.test with --flake8 and -vv then the tests run very slowly and it also uses a huge amount of RAM.
This is caused by flake8's extreme amount of debug sent stderr when run with -vv, which is in turn captured by py.test.
A workaround is to set -vv via addopts config which isn't detected by flake8 but still applies to py.test.
In testing with just 8 files this reduced the time to run from 16 seconds to just 1.
Are you sure this is not due to you perhaps having a .tox folder with (several?) full Python libraries it iterates into? If it is you might want to add .tox to your ignores so it does not descend into it at all...?
Have the same problem, no .tox in the project