protected void dump(Logger log) {
    getActive().dump(log);
    snapshot.dump(log);
  }
This method is protected under {@link HStore#lock} write lock,<br/>
and this method is used by {@link HStore#updateStorefiles} after flushing is completed.<br/>
The passed snapshot was successfully persisted; it can be let go.
@param id Id of the snapshot to clean out.
@see MemStore#snapshot()
hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/AbstractMemStore.java