IE9_h_cOne year ago today we showed the first look of the Chakra JavaScript engine that powers Internet Explorer 9 and people said it was fast.  They need to eat their words…it’s no longer fast…it’s faster than that…it’s the fastest JavaScript engine on earth according to the WebKit SunSpider micro-benchmark.  I’m sure the guys in the team will grab a beer coffee say “cheers!” and then go back to work.  They’ll be back at work for two reasons, the first is that IE9 gets innovation, blowing this micro-benchmark out of the water is just one sign.  The second reason is that they really get what speed is about and it’s not just about JavaScript, despite what some people will tell you. 

Measuring the performance of a browser, subsystem by individual subsystem, is inherently flawed because it’s not how real sites work and it doesn’t reflect how subsystems perform together.

So what else matters to real world performance if it’s not just JavaScript?  Well actually lots of aspects.  Hardware acceleration is a major factor and will be a rising star in performance terms as more websites use more complex HTML5.  Another is load time of the browser itself.  If you think about how you use your browser you tend to “dip in” when you need a web page so if you have the site you need pinned to your task bar then it’s faster to get loaded.  When you do Internet Explorer 9’s ability to monitor the performance of Add-ons and to disable the ones that seem to be stuck in the mud is a big help. 

A crude example of how much more there is to the web than just JavaScript is visible with almost any site if you hit F12 in Internet Explorer 9 and watch a network trace (not as complex as it sounds) you’ll be able to see that less than half of what’s loaded for a site like msn.co.uk is actually JavaScript, most of the site is words, layout and pictures.  That’s a typical story across the web.  All up speed matters more than just one element of the browser but it’s nice that Chakra is adding to that real world speed and is now 310% faster than it was a year ago when it was previewed at PDC according to this benchmark.

What can you do now?  You can try it for yourself at www.ietestdrive.com and just like the other previews it will run along side your current Internet Explorer install.