protected void notifyGatewaySender(EnumListenerEvent operation, EntryEventImpl event,
      boolean isLastEventInTransaction) {
    if (isPdxTypesRegion()) {
      return;
    }

    // Return if the inhibit all notifications flag is set
    if (event.inhibitAllNotifications()) {
      if (logger.isDebugEnabled()) {
        logger.debug("Notification inhibited for key {}", event);
      }
      return;
    }

    checkSameSenderIdsAvailableOnAllNodes();
    Set<String> allGatewaySenderIds;
    if (event.getOperation() == Operation.UPDATE_VERSION_STAMP) {
      allGatewaySenderIds = getGatewaySenderIds();
    } else {
      allGatewaySenderIds = getAllGatewaySenderIds();
    }

    List<Integer> allRemoteDSIds = getRemoteDsIds(allGatewaySenderIds);
    if (allRemoteDSIds != null) {
      for (GatewaySender sender : getCache().getAllGatewaySenders()) {
        if (allGatewaySenderIds.contains(sender.getId())) {
          // TODO: This is a BUG. Why return and not continue?
          if (!getDataPolicy().withStorage() && sender.isParallel()) {
            return;
          }
          if (logger.isDebugEnabled()) {
            logger.debug("Notifying the GatewaySender : {}", sender.getId());
          }
          ((AbstractGatewaySender) sender).distribute(operation, event, allRemoteDSIds,
              isLastEventInTransaction);
        }
      }
    }
  }
Returns true if this region notifies any serial gateway senders including internal async event
queues.
geode-core/src/main/java/org/apache/geode/internal/cache/LocalRegion.java