27 JS files including jQuery and Prototype!? Someone at North Face needs to do some refactoring, minify their code and figure out how to use one library instead of two.
4. Set max-age header for files to at least an hour
Any idea of what kind of performance bump could I expect from implementing this (assuming a similar profile to The North Face example)? I'd be interested in retooling some projects, but I'd only put in the time if the differences are material.
The one thing I would add is: wherever possible, give resources immutable URLs (that is, when a resource changes, change its URL) and tell the browser to cache them not for an hour but forever. This saves endless wailing and gnashing of teeth on both sides of the browser-cache abyss (i.e. things not being cached when you want them to and -- much worse -- things being cached when you don't want them to). Seriously, this rule changes misery to joy.
p.s. While copying the above link I noticed that Souders published a sequel (Even Faster Web Sites). Who here has read it? Can you report how good it is?
Even Faster is mostly JavaScript and image optimisations. Not quite the holy Grail of the first book but a good one to have in your collection none the less.
even faster summary:
install yslow and PageSpeed, follow recommendations.
I've seen enormous improvements on site which didn't follow any of this rules, something like load time divided by 2 or more, but of course it depends how bad is the site you start with.
Those plugins are great but you really need to look at the waterfall breakdown of your site to really grasp where best to spend your time. The net panel in firebug can be amazingly helpful at showing you where blocking and latency is causing the most grief.