public Stream<TRegionReplicaSet> getAllReplicaSets() {
    return regionGroupMap.values().stream().map(RegionGroup::getReplicaSet);
  }
@return Deep copy of all Regions' RegionReplicaSet within one StorageGroup
iotdb-core/confignode/src/main/java/org/apache/iotdb/confignode/persistence/partition/DatabasePartitionTable.java