RegionLoad.Builder setCompleteSequenceId(RegionLoad.Builder regionLoadBldr) {
    long lastFlushOpSeqIdLocal = this.lastFlushOpSeqId;
    byte[] encodedRegionName = this.getRegionInfo().getEncodedNameAsBytes();
    regionLoadBldr.clearStoreCompleteSequenceId();
    for (byte[] familyName : this.stores.keySet()) {
      long earliest = this.wal.getEarliestMemStoreSeqNum(encodedRegionName, familyName);
      // Subtract - 1 to go earlier than the current oldest, unflushed edit in memstore; this will
      // give us a sequence id that is for sure flushed. We want edit replay to start after this
      // sequence id in this region. If NO_SEQNUM, use the regions maximum flush id.
      long csid = (earliest == HConstants.NO_SEQNUM) ? lastFlushOpSeqIdLocal : earliest - 1;
      regionLoadBldr.addStoreCompleteSequenceId(StoreSequenceId.newBuilder()
        .setFamilyName(UnsafeByteOperations.unsafeWrap(familyName)).setSequenceId(csid).build());
    }
    return regionLoadBldr.setCompleteSequenceId(getMaxFlushedSeqId());
  }
@return the Region directory under WALRootDirectory
@throws IOException if there is an error getting WALRootDir
hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/HRegion.java