5be64ce4_Apache_HBase___Reference_Guide__Description
[Parameter] hbase.hstore.compaction.min.size [Default] 128 MB [Description] 
A StoreFile smaller than this size will always be eligible for minor compaction. StoreFiles this size or larger are evaluated by hbase.hstore.compaction.ratio to determine if they are eligible. Because this limit represents the "automatic include" limit for all StoreFiles smaller than this value, this value may need to be reduced in write-heavy environments where many files in the 1-2 MB range are being flushed, because every StoreFile will be targeted for compaction and the resulting StoreFiles may still be under the minimum size and require further compaction. If this parameter is lowered, the ratio check is triggered more quickly. This addressed some issues seen in earlier versions of HBase but changing this parameter is no longer necessary in most situations.
Apache HBase ™ Reference Guide
Description