Optimize Unturned Server

Hey guys, im hosting about 3 server Unturned, when my player reach about 40 in one server it will cause lag and stun both players and zombies. Meanwhile, my server resource still good (CPU: 40% and RAM 70%)

Anyone have the answer, please help me. Thanks

Sorry for my bad english. Hope you still understand my question.
image

Right click the cpu picture and change the view to lochical . You will see that one of your proc uses up all.
Unturned on MS Windows can only use 1 !

maybe you are right, i increase from 2Ghz per cpu to 3Ghz and it help me a little bit. But Unturned on Windows only use cpu 1 is wrong, because all of my cpus run in same usage.

Thank for helping me

Servers use only one thread. That one core is probably dying.