Well, I finally upgraded our source control to Team Foundation Server 2018. Not sure when, or if, I’ll upgrade to Azure DevOps Server 2019. This is a good next step at least, and it’s working pretty nicely.
The memory in the Team Foundation Server was upgraded to 12GB. That should be more than enough. The file server memory was also upgraded to 20GB. It will be able to cache a lot of files now!