为什么通过网络获取资源需要客户端和服务器之间的多次往返？
Why could fetching resources over the network require multiple roundtrips between the client and server?
我正在 https://developers.google.com/speed/docs/insights/LeverageBrowserCaching 阅读以下信息：
Fetching resources over the network is both slow and expensive: the download may require multiple roundtrips between the client and server, which delays processing and may block rendering of page content, and also incurs data costs for the visitor.
为什么会这样require multiple roundtrips？为什么不 a single roundtrip？
也许几个字节可以在一次往返中完成。然而，正如 Ilya Grigorik 在 https://developers.google.com/web/fundamentals/performance/optimizing-content-efficiency/http-caching#defining-optimal-cache-control-policy、"large responses require many roundtrips between the client and server".
中所述
我正在 https://developers.google.com/speed/docs/insights/LeverageBrowserCaching 阅读以下信息：
Fetching resources over the network is both slow and expensive: the download may require multiple roundtrips between the client and server, which delays processing and may block rendering of page content, and also incurs data costs for the visitor.
为什么会这样require multiple roundtrips？为什么不 a single roundtrip？
也许几个字节可以在一次往返中完成。然而，正如 Ilya Grigorik 在 https://developers.google.com/web/fundamentals/performance/optimizing-content-efficiency/http-caching#defining-optimal-cache-control-policy、"large responses require many roundtrips between the client and server".
中所述