protected boolean stillWaitingFromNodes() {
    if (shutdown) {
      // Create the exception here, so that the call stack reflects the
      // failed computation. If you set the exception in onShutdown,
      // the resulting stack is not of interest.
      ReplyException re = new ReplyException(new DistributedSystemDisconnectedException(
          "aborted due to shutdown"));
      exception = re;
      return false;
    }
    // return (numMembers()-this.numMemberDeparted) > 0;
    return numMembers() > 0;
  }
Overridden to wait for messages being currently processed: This situation can come about if a
member departs while we are still processing data from that member
geode-core/src/main/java/org/apache/geode/internal/cache/execute/FunctionStreamingResultCollector.java