Does CPU thread affect server FPS?
My cpu is E5-2690 v3. My server only got about 20fps when 20 players in game. But my friend E5-2667 v2 could get 600fps on same condition. Why is the difference so big? 

And if I only use one cpu thread to run server the fps will rise to about 100. Does CPU thread affect server FPS?
Both of those CPUs are going to be overkill for the Rust server, so it's unlikely that the variance there would make a difference. The Rust server runs in 2 cores max, with those CPUs having 8-12 cores each. While some of Rust and Unity are multithreaded, what those CPUs provide would still be more than what the server makes use of.

Keep in mind that one core is not the same as one thread.
5e13a8d5b2bc5.jpg Wulf
Both of those CPUs are going to be overkill for the Rust server, so it's unlikely that the variance there would make a difference. The Rust server runs in 2 cores max, with those CPUs having 8-12 cores each. While some of Rust and Unity are multithreaded, what those CPUs provide would still be more than what the server makes use of.

Keep in mind that one core is not the same as one thread.

Thanks!