@Override
  public synchronized boolean put(Object event) throws CacheException {
    GatewaySenderEventImpl eventImpl = (GatewaySenderEventImpl) event;
    final Region<?, ?> r = eventImpl.getRegion();
    final boolean isPDXRegion =
        (r instanceof DistributedRegion && r.getName().equals(PeerTypeRegistration.REGION_NAME));
    final boolean isWbcl =
        regionName.startsWith(AsyncEventQueueImpl.ASYNC_EVENT_QUEUE_PREFIX);
    if (!(isPDXRegion && isWbcl)) {
      putAndGetKey(event);
      return true;
    }
    return false;
  }
Whether the <code>Gateway</code> queue should be no-ack instead of ack.
geode-core/src/main/java/org/apache/geode/internal/cache/wan/serial/SerialGatewaySenderQueue.java