private void onAssignedHook(final PipeRealtimeEvent realtimeEvent) {
    realtimeEvent.gcSchemaInfo();
    realtimeEvent.decreaseReferenceCount(PipeDataRegionAssigner.class.getName(), false);

    final EnrichedEvent innerEvent = realtimeEvent.getEvent();
    eventCounter.decreaseEventCount(innerEvent);
    if (innerEvent instanceof PipeHeartbeatEvent) {
      ((PipeHeartbeatEvent) innerEvent).onAssigned();
    }
  }
The {@link DisruptorQueue} is used to assign the event to the extractor.
iotdb-core/datanode/src/main/java/org/apache/iotdb/db/pipe/extractor/dataregion/realtime/assigner/PipeDataRegionAssigner.java