Only 4 Cores reported to game

Hi,

I have a MBP 2023 M3 Max 64GB with 16 Core CPU ( 4 efficiency, 12 Performance) and 40C GPU.

I've got a Game (Cities Skylines 2) successfully working using Whisky. However, only 4 Cores are reported to the game which leads to a situation where there are many calculations batched up while at the same time my CPU performance cores almost idle, while the efficiency cores are well utilized.

I suspect this is because the game only sees 4 cores and has some logic to batch the calculations differently depending on how much cores are available.

Is there a way to override how many cores the game sees? e.g. by using an environment variable or something?

Thanks, Dominik