I have an azure general purpose managed instance, 8vCore, 1Tb storage running. The average CPU usage is 50%, with 70-75% in peak hours. Now we have a new report that need almost real-time data and since the server is heavy used, the query get a lot of concurrrency with writes tasks.
Noted that the business critical tier provides native high availability and reporting queries can be easily redirected to the free-of-charge secondary read-only replica. Also the BC tier provides a super-fast storage (local SSD) vs the actual remote storage. In that cenario I can separate read-write queries and read-only/analytic/reporting queries. At the end, it´s almost like getting twice the vCores and memory for the same price.
The question here resides in the comparison below:
Looking only for performance (do not consider the 500€ difference) should I make that change? In other works, less vCores, but faster storage subsystem and better hardware, should the 4 vCore BC tier performs better than a 8 vCore in general purpose tier? Considering that it´s 30% more expensive, I assume that the answer should be "yes", but would like to listen the experts opinions here.
Thanks a lot!