protected void syncStream(final FSDataOutputStream stream) throws IOException {
    if (useHsync) {
      stream.hsync();
    } else {
      stream.hflush();
    }
  }
Used to construct the name of the log directory for master procedures
hbase-procedure/src/main/java/org/apache/hadoop/hbase/procedure2/store/wal/WALProcedureStore.java