default long getLastMajorCompactionTimestamp(TableName table) {
    return getLiveServerMetrics().values().stream()
      .flatMap(s -> s.getRegionMetrics().values().stream())
      .filter(r -> RegionInfo.getTable(r.getRegionName()).equals(table))
      .mapToLong(RegionMetrics::getLastMajorCompactionTimestamp).min().orElse(0);
  }
Returns the names of backup masters
hbase-client/src/main/java/org/apache/hadoop/hbase/ClusterMetrics.java