Web Performance

"Smash PNGs for faster sites"

"platform closely monitors end-user performance and makes sure your content is always delivered by the fastest CDN. "

Summary: Learn how to simulate the elimination of JavaScript with Web Page Test. By eliminating, deferring or converting your JavaScript behavior into CSS you can speed up your page rendering and load times.

SPDY is a replacement for HTTP, designed to speed up transfers of web pages by eliminating much of the overhead associated with HTTP. SPDY supports several optimizations that give it an edge over HTTP when it comes to speed.

"Il existe une conviction partagée chez les grands du Web : la performance perçue par l'utilisateur est critique. Cette performance a en effet un impact direct sur l'adoption du service et son utilisation dans la durée. Et le ressenti utilisateur est directement lié à la rapidité d'affichage des interfaces."

Speed matters online. Study after study has shown that even 100 millisecond delays in load times negatively impact user experience and conversions. So it's no wonder that e-commerce experiences are particularly susceptible to performance as these recent bits of data illustrate. The average Internet connection speed around the world was 2.3 Mbps by the end of 2011.

"Web FontFonts speak many languages, but most of the time you only need a select few. Removing the letters you don't need can greatly reduce the font file size to make your websites faster, optimize bandwidth usage, and reduce high-traffic costs. "

Scripts tiers & appels induits

One of the fun things about Velocity is all the great tools that people unveil over the course of the conference. Here are three that I've checked out so far and liked. If you have any to recommend, let me know in the comments.

Yottaa is proud to introduce Websitetest.com, a free testing tool with multivariate testing capability. In a single test, see how your website performs across multiple locations, browsers, and connectivity types. Set tests to run in the future at time increments of your choice.

"Scour is an open-source Python script that aggressively cleans SVG files, removing a lot of 'cruft' that certain tools or authors embed into their documents. The goal of scour is to provide an identically rendered image"

At Bugsnag we use SPDY on our production rails application. For our users who run modern browsers, this can make the site feel much faster and more responsive. Want to get SPDY working on your production rails app? Read on. What is SPDY?

Outil d'analyse de fuite mémoire JavaScript dans le navigateur. C'est pas aussi aisé qu'un bookmarklet mais ça permet d'aller assez loin dans la détection de fuite.

August is Speed Awareness Month, and performance experts throughout our community are contributing their perspectives. My post about must-have mobile optimization techniques just went live. Here's the intro... As you probably know, mobile users face unique performance challenges when it comes to implementing the strategies above.

"Quand on parle des performances web, on peut risquer de trop idéaliser les conseils et bonnes pratiques. Cédric Morin vous propose cette semaine un article pragmatique qui vous aidera à mettre tout ceci en perspective, et à mieux gérer l'optimisation de vos sites."

"combining can sometimes make loads slower, due to deferral of JS execution (have to download entire combined JS file before any of the JS can be executed). A second reason is that combining can make the resources take longer to download, due to the way that TCP slow start works"