@TestOnly
  public TimePartitionInfo getTimePartitionInfo(DataRegionId dataRegionId, long timePartitionId) {
    synchronized (timePartitionInfoMap) {
      Map<Long, TimePartitionInfo> timePartitionInfoMapForDataRegion =
          timePartitionInfoMap.get(dataRegionId);
      if (timePartitionInfoMapForDataRegion == null) {
        return null;
      }
      return timePartitionInfoMapForDataRegion.get(timePartitionId);
    }
  }
Manage all the time partitions for all data regions and control the total memory of them
iotdb-core/datanode/src/main/java/org/apache/iotdb/db/storageengine/rescon/memory/TimePartitionManager.java