I noticed a lot of hitching on my server yesterday -- just had a total of 3 people connected to the server. The server itself is old hardware -- a Core 2 Quad running FreeBSD and using the Linux emulator to run the game.
I noticed that the Sandstorm server software was using 25% CPU, but the game would hitch occasionally. That seems to me that the server software is running on only one core.
So, is the server software multithreaded? If so, is there a way to enable that? (Similar to the "-USEALLAVAILABLECORES" option for the game itself (see: this Reddit post )
I know my server needs an upgrade; I'm just dreading that, heh. I've been hosting an Insurgency 1 server for a couple years on this hardware without any problems at the moment.