- From: Kornel Lesiński <kornel@geekhood.net>
- Date: Wed, 10 Jul 2013 17:56:49 +0100
- To: whatwg@lists.whatwg.org
- Cc: Kyle Simpson <getify@gmail.com>
On Wed, 10 Jul 2013 16:39:42 +0100, Kyle Simpson <getify@gmail.com> wrote: > I personally don't care about scripts being discoverable by pre-parsers. [...] > For instance, I've added like <link rel=prefetch> annotations for my > scripts into the head of my document, and then done my normal > script-based script loading as usual, and benchmarked if them being in > the markup somehow magically sped up the page. I saw no appreciable > increase in average page load speed in my testing. The result you've seen is expected, as pre-parser and link prefetching are different mechanisms. Prefetching of resources from rel="prefetch" is only done after page completely finishes loading, so it won't affect loading time of page that contains it (it's for future navigation, like "step1.html" containing prefetch for "step2.html"). There's rel="subresource" that's for immediate prefetching in the way you'd expect. You should see some improvement with it in cases where script loader makes it impossible for browser to start fetching scripts before the script loader is run: http://www.chromium.org/spdy/link-headers-and-server-hint/link-rel-subresource HTML pre-parser is basically equivalent of having rel="subresource" for all <script> elements. -- regards, Kornel
Received on Wednesday, 10 July 2013 16:58:06 UTC