What's the best way to determine at runtime if a browser is too slow to gracefully handle complex JavaScript/CSS?

Question

I\'m toying with the idea of progressively enabling/disabling JavaScript (and CSS) effects on a page - depending on how fast/slow the browser seems to be.

I\'m speci

Answer 1

You could try timing some basic operations - have a look at Steve Souder's Episodes and Yahoo's boomerang for good ways of timing stuff browserside. However its going to be rather complicated to work out how the metrics relate to an acceptable level of performance / a rewarding user experience.

If you're going to provide a UI to let users opt in / opt out, why not just let the user choose the level of eye candy in the app vs the rendering speed?