Question Semaphore.WaitForSignal causing FPS drop, but when I use GPU Profiler, FPS increased

I'm suffering huge FPS issue. I tried making a scene with nothing but UI canvas and an Image, but it still only reaches 30 FPS. I tried checking every setting in Project Setting and scene setup that I use in my other projects that didn't have this issue, but I couldn't find anything. Same setting, same setup, but only this project is broken while others work fine



I try to diagnose and turn on GPU Usage. Suddenly the FPS increased from 30 to 60!


What is Semaphore.WaitForSignal doing to consume so much performance? I can't figure out why I have this problem only in one project while my other projects don't have it

 

I fixed it. I disabled "Optimized Frame Pacing" in Project Setting > Player > Resolution and Presentation.