I'm thinking about setting up my own dedicated server for the purpose of hosting large games, rather than depend on my local. What sort of metrics can I look to record on the server in terms of understanding performance? Obviously I can just play, play, play and try and note down my observations of game speed, but that seems terribly time-consuming. I suppose I can measure system level metrics such as CPU / memory usage, and if those are getting saturated I suppose I'm at / below potential, and if utilization is low, then I have more head room to increase game size. Do / can server logs spit out more meaningful information though?
You should ping @cola_colin about this as he did some extensive testing on a large core count server. What you need does relate to how many players you want (custom servers don't have a restriction on player count, we have successfully held 40+ player games this way). I know one of the biggest requirements is as strong as possible single thread performance as the physics simulation is single core. Multi core does help for large number of players as the network side uses lots of threads. The other main requirements are lots of bandwidth (especially upload for sending updates to clients) and plenty of ram. Server doesn't need a GPU I don't think.
Take a look through this thread: https://forums.uberent.com/threads/regular-large-15-32-player-ffa-and-team-games-on-weekends.68242/
