Game is "Lagging" when using Screen Capture (XSHM)

[dom1orii]

I wanna use replay buffer in OBS and capture whole screen with it using Screen Capture (XSHM). But in games that use 99% GPU (for example CS2) my game starts lagging but i get no fps drops. I noticed that if i set fps limit so game doesn't use 99% GPU it stops lagging, so its obviously problem with game using 99% GPU, but i can't do this because game will be unplayable for me. What do i do? Is there any good fix for this?