public static String formatBulkloadSeqId(long seqId) {
    return SEQ_ID_MARKER + seqId + "_";
  }
@see #SEQ_ID_MARKER
@return A string value for appending to the end of a bulkloaded file name, containing the
        properly formatted SeqId marker.
hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/StoreFileInfo.java