Like C language index 1st core is 0, 2nd core is 1, and so on.
=1 - core 0
=2 - core 1
=3 - core 0+1
=4 - core 2
=5 - core 0+2
=6 - core 1+2
=7 - core 0+1+2
if commented out by ; -> use all cores
IL-2 can run in multi-core but it do not benefit single fps gain from it.
Assign it to 2nd core or else and make OS thingys run at 1st core, just to secure some more smoothness.
So I use it with
ProcessAffinityMask=2
To AstroCat, I use
MTRON SLC SSD 32GB which has good controller tech in it.
I don't know they sell it in your country.
Funny thing is DCS Black Shark get fps increase about 50% to 70% by using both cores. It's great.
IL-2 never benefit like other ordinary games, so don't take too much concern about it.