Hacker News Reader

I wonder...

http://www.yoav.ws/2012/05/Responsive-image-format

Yup I'm not the only person to come-up with this. I think heuristically guessing how much to request from the content-length with two range requests would work just fine.

View on HN

When it comes to page load speed, extra network round trips are really bad. Even if you're loading the same total amount of data.

But it can keep the port open so a few round trips are saved, it might be fast enough to make the second request while the first was still coming in so effectively very little overhead, even on (especially on) high latency links where it matters most. It can start drawing even from the first range request, and the idea is to never pull down the entire file (for big files, the case you are optimizing anyway, small ones you don't really need to) and only maybe end-up pulling in the entire hires file with a third request if say the user zooms way in.

Reply on news.ycombinator.com