too many open files after upgrading to Pest 2, phpunit 10

[Gompje]

fyi: This is big project, I know it has some legacy code and its not all optimized. it has pest tests, and normal php unit tests mixed together.

However since I upgrade to the newer versions of both, I get a too many open files error on my machine when running in parallel. That's MacAir 2020 M1. processes used is 8

I know I can change the limit with

ulimit -n 10000

but I think this gets reset again after reboot/update/idk.

I would appreciate if anyone can share an insight why this is now a problem, aka after bumping the version; while before it was not. I could add a script to reset it when starting the computer but I would really like to know why this is now an issue 😊

edit: on v1 I was using the parallel plugin