@Override
  public void stop() {
    this.threads.forEach(
        t -> {
          try {
            t.close();
          } catch (IOException e) {
            // Only a field is set, there's no chance to throw an IOException
          }
        });
  }
The manager of fragment instances scheduling.
iotdb-core/datanode/src/main/java/org/apache/iotdb/db/queryengine/execution/schedule/DriverScheduler.java