private void syncReleaseFlushedMemTable(IMemTable memTable) {
    synchronized (flushingMemTables) {
      releaseFlushedMemTable(memTable);
      flushingMemTables.notifyAll();
      if (logger.isDebugEnabled()) {
        logger.debug(
            "{}: {} released a memtable (signal={}), flushingMemtables size ={}",
            dataRegionName,
            tsFileResource.getTsFile().getName(),
            memTable.isSignalMemTable(),
            flushingMemTables.size());
      }
    }
  }
This method will synchronize the memTable and release its flushing resources
iotdb-core/datanode/src/main/java/org/apache/iotdb/db/storageengine/dataregion/memtable/TsFileProcessor.java