The same async program run on (Linux+AMD) vs (Win+Intel), over 6x performance difference

[sgaure]

There was a recent thread about something similar. I have not used windows, so don’t know anything about whether it’s related.

Performace problems with Windows scheduler and multithreading on mixed core CPUs

I have a function with a long running simulation (> 20 min) and used Threads@spawn to start four of them in parallel. Disappointingly the runtime more than doubled compared to a single instance run. After some digging I found out that the Windows scheduler had placed all four compute threads on the four small Zen 5c CPUs of my laptop while the four big cores were idle… If I set the priority of the julia process to high by hand in the taskmanager the threads are migrated over to the big cores an…