如何优化 UITextView 以阻止滞后？

问：

最近，我构建了一个带有 UITextView 的视图控制器。逻辑很简单，在 viewDidLoad 中有一个 API 调用来从 db 获取歌词。可以在下面找到管理 UITextView 设置的整个代码。

override func viewDidLoad() {
        super.viewDidLoad()
        
        Track(id: track!.id).getLyrics { [self] response in
            guard let text = response?.lyrics_text else { return }
            
            var writtenBy = response?.lyrics_writers ?? ""
            
            if writtenBy.isEmpty {
                writtenBy = track?.album?.artistsString() ?? ""
            }
            
            let style = NSMutableParagraphStyle()
            style.lineSpacing = 10
            let attributes = [
                NSAttributedString.Key.font: UIFont(name: "Helvetica", size: 19),
                NSAttributedString.Key.foregroundColor: UIColor(named: "Primary Material"),
                NSAttributedString.Key.paragraphStyle: style
            ]
            
            let attributedText = NSMutableAttributedString(string: writtenByPhrase+" "+writtenBy+"\n\n"+text, attributes: attributes as [NSAttributedString.Key : Any])
            
            attributedText.addAttribute(.font, value: UIFont(name: "Helvetica-Bold", size: 19) as Any, range: NSRange(location: 0, length: writtenByPhrase.count))
            
            textView?.attributedText = attributedText
            
            textView?.textContainer.lineFragmentPadding = 20
            textView?.textContainerInset.top = 20
            textView?.textContainerInset.bottom = 200
            
            textView?.scrollRangeToVisible(NSRange(location: 0, length: 0))
        }
}

当我在真实设备上测试它并滚动浏览内容时，我想它第一次在预加载到内存时会滞后。但是，当您已经滚动浏览了所有内容时，滚动开始变得流畅。

如何设法消除第一次滚动的滞后？