4 ms·

Those page load improvement numbers seem ridiculously good (factor of almost 2 versus HTTP 1.1). Are they really expecting that to hold up in real world cases?

by tgb 11y ago

therealmarv 11y ago
You see nearly 90% of this improvements already for years with SPDY. SSL with HTTP 1.1 was really slow before Google, FB etc. starting using SPDY years ago. So comparing HTTP 1.1 with SSL to HTTP/2 with SSL seems legit for me.
- rplnt 11y ago
  I thought HTTP/2 was going to be SSL only? Or was that other protocol?
  - therealmarv 11y ago
    SPDY only runs encrypted. The HTTP/2 specification allows it to run without encryption https://http2.github.io/faq/#does-http2-require-encryption https://http2.github.io/faq/#does-http2-require-encryption But most of the browser vendors will only allow to use it with encryption (see footnotes here): http://caniuse.com/#search=http%2F2 http://caniuse.com/#search=http%2F2
    - magicalist 11y ago
      Note that the caniuse data is slightly wrong. All browsers only support HTTP/2 over TLS. (there's an issue to fix that on the caniuse github repo: https://github.com/Fyrd/caniuse/issues/2098 https://github.com/Fyrd/caniuse/issues/2098)
contravariant 11y ago
In their demo[1] it is 20x faster for me, I had to disable http pipelining for it to work correctly (not sure why, but http/2 became a lot faster after I had disabled pipelining). Minor nitpick: I don't agree with the way they calculate the percentage, if it takes 5% of the time then it's 20x (i.e. 1900%) faster, not 95%. [1]: https://www.cloudflare.com/http2/ https://www.cloudflare.com/http2/
- deleted 11y ago
  [deleted]
- stock_toaster 11y ago
  Oddly their demo shows Safari 9 (el cap) as not supporting http/2, but only spdy. Other test sites (akamai) show safari using http/2 just fine -- safari does appear (wireshark capture) to be sending the tls alpn h2 thingy.
  - eastdakota 11y ago
    There appears to be a weird bug we're trying to track down with Safari + IPv6 resulting in connections using SPDY when they should use HTTP/2. We're trying to track down whether it's on our side or Apple's.
    - stock_toaster 11y ago
      Interesting! Thanks for the info.
- bsdetector 11y ago
  Isn't it interesting that even today, after Microsoft Research showed that pipelining could be almost as fast as SPDY and when activating it in Firefox is an about:config away, people still refuse to include it in any tests? Google never showed any results vs pipelining. They just said "head of line blocking bad" and "one TCP connection per user good" (for tracking) and people just ate it up without evidence because, I suppose, they viewed HTTP/2 as conceptually simpler and more elegant. Nevermind that HTTP/2 didn't address any criticism that PHK had... that's ok because Google was just going to do it anyway.
  - e12e 11y ago
    If anyone else wants a bit of history on pipelining wrt Netscape/Firefox etc: http://kb.mozillazine.org/Network.http.pipelining http://kb.mozillazine.org/Network.http.pipelining And in particular (from links in the above): "Bug 264354 - Enable HTTP pipelining by default Status: RESOLVED WONTFIX" - in particular one of the last comments in the thread: https://bugzilla.mozilla.org/show_bug.cgi?id=264354#c65 https://bugzilla.mozilla.org/show_bug.cgi?id=264354#c65 And: "Bug 395838 - Remove HTTP pipelining pref from release builds Status: RESOLVED WONTFIX": https://bugzilla.mozilla.org/show_bug.cgi?id=395838 https://bugzilla.mozilla.org/show_bug.cgi?id=395838 My general impression is that there were a few issues on Windows, in particular with "anti-virus software", and some problems with broken proxies -- as well as a handful of issues with hopelessly broken servers. Additionally, it appears SSL/TLS latency was never really considered (not explicitly stated, but there appear to be implications that on "fast networks" http is "fast enough" that pipelining makes little difference) -- in other words it does indeed appear that just enabling piplining as the web moved from plain http to TLS, would've sidestepped most of the need for HTTP/2...

Those page load improvement numbers seem ridiculously good (factor of almost 2 versus HTTP 1.1). Are they really expecting that to hold up in real world cases?

by tgb 11y ago

Those page load improvement numbers seem ridiculously good (factor of almost 2 versus HTTP 1.1). Are they really expecting that to hold up in real world cases?

therealmarv 11y ago

You see nearly 90% of this improvements already for years with SPDY. SSL with HTTP 1.1 was really slow before Google, FB etc. starting using SPDY years ago. So comparing HTTP 1.1 with SSL to HTTP/2 with SSL seems legit for me.

rplnt 11y ago
I thought HTTP/2 was going to be SSL only? Or was that other protocol?
- therealmarv 11y ago
  SPDY only runs encrypted. The HTTP/2 specification allows it to run without encryption https://http2.github.io/faq/#does-http2-require-encryption https://http2.github.io/faq/#does-http2-require-encryption But most of the browser vendors will only allow to use it with encryption (see footnotes here): http://caniuse.com/#search=http%2F2 http://caniuse.com/#search=http%2F2
  - magicalist 11y ago
    Note that the caniuse data is slightly wrong. All browsers only support HTTP/2 over TLS. (there's an issue to fix that on the caniuse github repo: https://github.com/Fyrd/caniuse/issues/2098 https://github.com/Fyrd/caniuse/issues/2098)

contravariant 11y ago

In their demo[1] it is 20x faster for me, I had to disable http pipelining for it to work correctly (not sure why, but http/2 became a lot faster after I had disabled pipelining). Minor nitpick: I don't agree with the way they calculate the percentage, if it takes 5% of the time then it's 20x (i.e. 1900%) faster, not 95%. [1]: https://www.cloudflare.com/http2/ https://www.cloudflare.com/http2/

deleted 11y ago
[deleted]
stock_toaster 11y ago
Oddly their demo shows Safari 9 (el cap) as not supporting http/2, but only spdy. Other test sites (akamai) show safari using http/2 just fine -- safari does appear (wireshark capture) to be sending the tls alpn h2 thingy.
- eastdakota 11y ago
  There appears to be a weird bug we're trying to track down with Safari + IPv6 resulting in connections using SPDY when they should use HTTP/2. We're trying to track down whether it's on our side or Apple's.
  - stock_toaster 11y ago
    Interesting! Thanks for the info.
bsdetector 11y ago
Isn't it interesting that even today, after Microsoft Research showed that pipelining could be almost as fast as SPDY and when activating it in Firefox is an about:config away, people still refuse to include it in any tests? Google never showed any results vs pipelining. They just said "head of line blocking bad" and "one TCP connection per user good" (for tracking) and people just ate it up without evidence because, I suppose, they viewed HTTP/2 as conceptually simpler and more elegant. Nevermind that HTTP/2 didn't address any criticism that PHK had... that's ok because Google was just going to do it anyway.
- e12e 11y ago
  If anyone else wants a bit of history on pipelining wrt Netscape/Firefox etc: http://kb.mozillazine.org/Network.http.pipelining http://kb.mozillazine.org/Network.http.pipelining And in particular (from links in the above): "Bug 264354 - Enable HTTP pipelining by default Status: RESOLVED WONTFIX" - in particular one of the last comments in the thread: https://bugzilla.mozilla.org/show_bug.cgi?id=264354#c65 https://bugzilla.mozilla.org/show_bug.cgi?id=264354#c65 And: "Bug 395838 - Remove HTTP pipelining pref from release builds Status: RESOLVED WONTFIX": https://bugzilla.mozilla.org/show_bug.cgi?id=395838 https://bugzilla.mozilla.org/show_bug.cgi?id=395838 My general impression is that there were a few issues on Windows, in particular with "anti-virus software", and some problems with broken proxies -- as well as a handful of issues with hopelessly broken servers. Additionally, it appears SSL/TLS latency was never really considered (not explicitly stated, but there appear to be implications that on "fast networks" http is "fast enough" that pipelining makes little difference) -- in other words it does indeed appear that just enabling piplining as the web moved from plain http to TLS, would've sidestepped most of the need for HTTP/2...