code: func (a *HorizontalController) Run(stopCh <-chan struct{}) {
  	defer utilruntime.HandleCrash()
  	defer a.queue.ShutDown()
  
  	klog.Infof("Starting HPA controller")
  	defer klog.Infof("Shutting down HPA controller")
  
  	if !controller.WaitForCacheSync("HPA", stopCh, a.hpaListerSynced, a.podListerSynced) {
  		return
  	}
  
  	// start a single worker (we may wish to start more in the future)
  	go wait.Until(a.worker, time.Second, stopCh)
  
  	<-stopCh
  }
docs: // Run begins watching and syncing.