@Override
  public void sampled(long nanosTimeStamp, List<ResourceInstance> resourceInstances) {
    synchronized (this) {
      if (enableMonitorThread) {
        final StatMonitorNotifier thread = notifier;
        if (thread != null) {
          try {
            thread.monitor(new MonitorTask(System.currentTimeMillis(), resourceInstances));
          } catch (InterruptedException e) {
            Thread.currentThread().interrupt();
          }
        }
      } else {
        monitor(System.currentTimeMillis(), resourceInstances);
      }
    }
  }
Stops the notifier thread if one exists.
geode-core/src/main/java/org/apache/geode/internal/statistics/StatMonitorHandler.java