@Override
  public void toData(DataOutput out,
      SerializationContext context) throws IOException {
    super.toData(out, context);
    DataSerializer.writeHashMap(regionToDispatchedKeysMap, out);
  }
Removes a batch of events from the remote secondary queues

@since GemFire 8.0
geode-core/src/main/java/org/apache/geode/internal/cache/wan/parallel/ParallelQueueRemovalMessage.java