public static void doneProcessing(DistributionMessage message) {
    if (message instanceof MessageWithReply) {
      INSTANCE.processingMessages.set(null);
    }
  }
This class keeps track of the information we need to determine which threads in the receiver
system a reply processor thread is waiting for.

This will allow us to programatically discover deadlocks.
geode-core/src/main/java/org/apache/geode/distributed/internal/deadlock/MessageDependencyMonitor.java