Your HBase cluster has hit a performance wall and doesn’t seem to be getting faster as you add
RegionServers. Adding an additional HMaster will:

A.
Have no effect on performance.

B.
Improve the performance of region writes but decrease the performance of metadata changes.

C.
Improve the performance of metadata chancier, but decrease the performance of region writes.

D.
Make the performance problem even worse, as operations will have to be replicated to multiple
masters.

Explanation:
You can add multiple HBase master nodes; however, only one HBase master node
is active at a time. The active HBase master node changes only when the current active HBase
master node is shut down or fails.