Why is my server at 100% CPU usage?

Don't panic if your server is using over 100% CPU, although this is not ideal, your server should perform just fine. You may assume 100% CPU usage means the node's CPU is being completely used by your server, it is not- 100% only refers to 1 thread of the node's CPU. Unlike storage, we do not limit CPU usage but you may find as your CPU usage increases above 250% that your server begins to lag.

You can find a guide for optimising your server here.