As a distributed cluster, HBase distribute loads in unit of region, so if region grows too big,
it will bring some negative effects, such as:
1. Harder to homogenize disk usage(consider locality)
2. Might cost more time on region opening
3. After split, the daughter region might lead to more io cost on compaction in a short time(if write evenly)
I tried to introduce a new SteppingAllStoresSizeSplitPolicy in
HBASE-24530, but after discussed in comments and related thread, finally we decide to change the existing split policy with a new option that if it should count all store files, and for master it would be true, else false.