code: func (s *Server) syncLoopHealthCheck(req *http.Request) error {
  	duration := s.host.ResyncInterval() * 2
  	minDuration := time.Minute * 5
  	if duration < minDuration {
  		duration = minDuration
  	}
  	enterLoopTime := s.host.LatestLoopEntryTime()
  	if !enterLoopTime.IsZero() && time.Now().After(enterLoopTime.Add(duration)) {
  		return fmt.Errorf("sync Loop took longer than expected")
  	}
  	return nil
  }
docs: // Checks if kubelet's sync loop  that updates containers is working.