what is the FPS and tick?

i understand FPS but im confused on what Tick is

our servers at 51 fps, and 11 tick always, is that bad?

Rusts standard tickrate (server.tickrate) is 10. I dont have try to set this up and what happened than. It means the game data refresh 10 times a second what is very slow. In my experience it starts lagging at 30 fps. So you don't have much air. It also depends on what you're up to. How many players, how many plugins, map size. I had a 30 dollar/month server that also brought 50 fps. With 20 players and a few plugins on a small procedural map it was over. I then moved to a stronger one that achieves around 220 fps with 180 plugins and a custom 5000 map actually. Specs: Dedicated Server - Core i7 - 12700k 60GB RAM Hope this could help you. (Just my experience!)

ty, 

the one servers not as powerful as the other

the other server we have is a 256Gb ram, 2Tb storage, i9 current gen and Realtime CPU, i get 300~ fps on that server with 200+ plugins