Options to increase HBase Region count and size
If you are an administrator, you cannot directly configure the number of regions for a RegionServer, however, you can indirectly increase the number of regions by increasing the size of the MemStore for a RegionServer and the size of the region.
In general, an HBase cluster runs more smoothly with fewer regions. You can also increase the number of regions for a RegionServer by splitting large regions to spread data and the request load across the cluster. HBase enables you to configure each HBase table individually, which is useful when tables have different workloads and use cases. Most region settings can be set on a per-table basis by using HTableDescriptor class, as well as by using the HBase CLI. These methods override the properties in the hbase-site.xml configuration file. For further information, see configure compactions.
The HDFS replication factor defined in the previous table affects only disk usage and should not be considered when planning the size of regions.