MySQL 8 Administrator???s Guide

Write scalability

Distribute your write workload by sharing out write operations, which might result in better throughput and better scalability on write performance. It would be dependent on contradictory workloads that you would be expecting in the system. This is helpful when your peak workload is being executed is one that can share the load. In common cases, if you have good capacity planning done with write scalability, you would see trivial improvement.

Refer to the following diagram that depicts this:

You will notice that with the help of multi-masters to distribute, your load has better throughput. It also considers the group size ...