CPU consumption can be 1 of 2 things:
1. There are programs, jobs, and etc... that are running in the project that requires CPU. Or there can be a ton of points being historized that are being updated.
2. The CPU is too slow for the project's demands.
We recommend using as much Heap Space as necessary for the server. You wont be able to see the actual application consumption by looking at these tools in the OS.
When you set the heap space, this tells the JVM that it can request that much memory, but the application running inside the JVM will be using much less. If there is a problem here you will see "out of memory" errors traced to the logs.