If you have a core license for Tableau Server, any node that has a "licensed process" running on it will then have its cores count towards the overall count core.
Here are the list of processes and the table shows which count against licensing and those that don't
Tableau Server Processes
If you were to add just one process that is considered licensed to your Primary then the cores of your Primary would be counted. Which could put you over. For example, let's say all of your nodes are 8core and you have a 24core license. In your current situation your 3 workers will add up to 24cores and you're good. But if you add a licensed process to your Primary, then in total you now have 32cores that count but your license is only valid for 24cores and there should be a "mismatch" error that occurs.
Thank you for explaining me in detail. I got it. One more thing, do we have any cores calculation based on the licensed processes? Say, I added one bg in primary. Will that count all 8 cores or any thing less in number?
It would be a cool feature if it worked the way you describe but in this case it really is "all or nothing", in that if just one licensed process is added to a node in a Tableau cluster the cores do get added. From the one snippet in OnlineHelp:
If you have a core-based Tableau Server license, the cores on any node with a licensed process will count against the total count of licensed cores.
Okay..Thanks mark for investing your time on this. It was very helpful.