问AdMob Ios导致的帧速率下降

EN

func initializeBanner() {
    // Create a banner ad and add it to the view hierarchy.
    bannerView.adUnitID = "ca-app-pub-8237297232584070/6035957145"
    bannerView.rootViewController = viewController
    bannerView.frame = CGRect(x:0.0,
                              y:(self.view?.frame.size.height)! - bannerView.frame.size.height,
                              width:bannerView.frame.size.width,
                              height:bannerView.frame.size.height)
}
func loadRequest() {
    let request = GADRequest()
    request.testDevices = [kGADSimulatorID]
    bannerView.load(request)
}
func createAd(){
    initializeBanner()
    loadRequest()
    openAdd()
}
func openAdd(){
    view!.addSubview(bannerView)
}