private HDFSBlocksDistribution computeHDFSBlocksDistributionInternal(final FileSystem fs)
    throws IOException {
    FileStatus status = getReferencedFileStatus(fs);
    if (this.reference != null) {
      return computeRefFileHDFSBlockDistribution(fs, reference, status);
    } else {
      return FSUtils.computeHDFSBlocksDistribution(fs, status, 0, status.getLen());
    }
  }
Compute the HDFS Block Distribution for this StoreFile
hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/StoreFileInfo.java