查看“︁HTTP pipelining”︁的源代码

HTTP pipelining is a feature of HTTP/1.1, which allows multiple HTTP requests to be sent over a single TCP connection without waiting for the corresponding responses.

HTTP/1.1 requires servers to respond to pipelined requests correctly, with non-pipelined but valid responses even if server does not support HTTP pipelining. Despite this requirement, '''many legacy [[HTTP/1.1]] servers do not support pipelining correctly, forcing most HTTP clients to not use HTTP pipelining'''.

The technique was superseded by '''multiplexing''' via [[HTTP/2]], which is supported by most modern browsers.

In [[HTTP/3]], multiplexing is accomplished via [[QUIC]] which replaces [[TCP]]. This further reduces loading time, as there is no [[Head-of-line blocking]] even if some packets are lost.

[[Image:Bonus1_H1_pipelining.png|600px|border]]

Crucially however, this pipelining only applies to the requests from the browser. As the HTTP/1.1 specification says:

‎<blockquote>A server MUST send its responses to those [pipelined] requests in the same order that the requests were received.</blockquote>

As such, we see that actual multiplexing of response chunks is still not possible with HTTP/1.1 pipelining. Put differently: pipelining solves HOL blocking for requests, but not for responses. Sadly, it’s arguably the response HOL blocking that causes the most issues for Web performance.
<ref>https://calendar.perfplanet.com/2020/head-of-line-blocking-in-quic-and-http-3-the-details/</ref>


[[Category:Network]]
[[Category:Protocol]]
[[Category:RFC]]
[[Category:HTTP]]