Do you have devices enrolled in this server? If so how many macOS and iOS?

Yes, 146 macOS, 0 iOS.

Edit: will be adding more macOS this summer and might toss some iOS devices on for testing.

Is everything running on the one server? 2GB isn't going to cut it, and depending on how often devices are communicating to Jamf Pro, and how many you add, 4GB probably won't be enough either. Have you opened a case with Jamf Support yet to get their recommendations?

The more users you have using the console, enrolled, executing policies, etc, the more ram will be used. 8GB ram is considered the minimum for building home computers at this point, do not be surprised if an enterprise server is going to consume ram like it is going out of style.

Almost as if it using it but not freeing it once done

why would you want it to be freed? having it inactive but still retaining information will make the server run "faster" for users on the web console since it does not have to reload everything in to memory.

I would love to take it down to 2 but 4 is fine

again - why? are you short on memory in your virtual environment? if so, you'll need to expand that or get dedicated hardware for your JSS (or have it cloud hosted if you feel strongly about that). your usage is only going to go up, not down, as you add devices and additional jamf pro users into your environment.

I understand. It would be hard to tell how many users, over 5K students enrolled. I'm not short on memory I am going to keep it at 8gigs. I still have not gone over 5gigs of use but 8 seems to run very well. My host has 64gigs total and I think 20gigs available. Can always add more if needed in the future. Thanks for the replies and information, was helpful.