Faster JavaScript with Safari/WebKit SquirrelFish

Webkit is the opensource engine behind Apple's Safari web browser for Mac, PC and the iPhone. Originally based on the KHTML engine from the KDE project, it has seen rapid development since the Safari 2.0 days.

In June, the project announced SquirrelFish, the oddly named next-gen JavaScript engine which includes bytecode compilation and a number of optimisations. The announcement indicates a 1.7 x speed increase over the engine in Safari 3.0. My perceptual testing on my (admittedly low baseline) G4 PPC powerbook suggests that startup time of JavaScript intensive applications such as Gmail improves only a little (saving 1 second off the 9 second startup time), but the ongoing performance is much snappier. Things like Flickr badges load in a snap.

It is good to get closer to the performance Firefox 3.0 which has the maddening property that it starts out very fast (7 second Gmail startup), but a large amount of JavaScript intensive browsing brings it to its knees over time - something Safari suffers far less from.

You can get a hold of the new engine by downloading the WebKit knightly build from http://webkit.org/