Hacker News Reader

Interesting to see that the parsing does not work on a stream anymore, but on a whole 'file'.

This gives up the real world optimisation of starting work on a partially downloaded file on slow network connections.

Even fast internet connections take a while to download 1MB of javascript. Not to mention the majority of internet users on slower connections.

I think this work could be improved to go back to the old behaviour.

View on HN

According to the stats gathered by HTTP Archive, the average response size (i.e. after compression) of a JavaScript file is 15kB: http://httparchive.org/interesting.php#responsesizes

This will make JavaScript parsing faster for the vast majority of sites, and for the majority of users.

If you have a single JavaScript file that is 1MB after gzipping, you really should think about modularising your code and lazy-loading the bits that aren't immediately required. See http://ajaxpatterns.org/On-Demand_Javascript

Also, don't forget that in most cases the JS code is probably loaded from the browser's cache anyway.

That optimization never existed for <script> loads in Gecko in the first place.

And it turns out that the optimization is overrated, especially for the common case of the 1MB file being in your cache anyway.

Reply on news.ycombinator.com