- From: Maciej Stachowiak <mjs@apple.com>
- Date: Mon, 03 Dec 2012 21:57:08 -0800
- To: William Chan (陈智昌) <willchan@chromium.org>
- Cc: whatwg@whatwg.org, Adam Barth <w3c@adambarth.com>
On Dec 3, 2012, at 2:11 PM, William Chan (陈智昌) <willchan@chromium.org> wrote: > Unless I am misunderstanding, SPDY will not solve this problem. SPDY uses > prioritized multiplexing of streams. It seems to me like SPDY could make this case work better: <script async src="path/to/script-part1.js"></script> <script async src="path/to/script-part2.js"></script> <script async src="path/to/script-part3.js"></script> Specifically the individual script chunks could be ordered and prioritized such that all of script-part1.js transfers before any of script-part3.js. That's harder to do with HTTP because the scripts could be loading on wholly separate HTTP connections, while SPDY will use one connection to the server. That being said, I do not know if SPDY will actually achieve this. Presumably it makes sense for it to serialize within a given priority level, at least a priority level that's likely to correspond to resources that are only atomically consumable, like scripts. But I don't know if SPDY implementations really do that. - Maciej > Generally speaking, a browser will map > a single resource request to a single stream, which would prevent chunked > processing by the browser without multipart/mixed. One could imagine > working around this by splitting the single resource into multiple > resources, and then relying on SPDY priorities to ensure sequential > delivery, but that is suboptimal due to having limited priority levels (4 > in SPDY/2, 8 in SPDY/3), and many of them are already used to indicate > relative priority amongst resource types ( > https://code.google.com/p/chromium/source/search?q=DetermineRequestPriority&origq=DetermineRequestPriority&btnG=Search+Trunk > ). > > > On Mon, Dec 3, 2012 at 1:40 PM, Anne van Kesteren <annevk@annevk.nl> wrote: > >> On Mon, Dec 3, 2012 at 10:14 PM, Adam Barth <w3c@adambarth.com> wrote: >>> The HTTP server would then break script.js into chunks that are safe >>> to execute sequentially and provide each chunk as a separate MIME part >>> in a multipart/mixed response. >> >> Is it expected that SPDY will take much longer than getting this >> supported in all browsers? Or am I missing how SPDY will not address >> this problem? >> >> >> -- >> http://annevankesteren.nl/ >>
Received on Tuesday, 4 December 2012 05:57:48 UTC