Does Silverlight have a performance advantage over JavaScript?

Question

At a recent discussion on Silverlight the advantage of speed was brought up. The argument for Silverlight was that it performed better in the browser than Javascript because it is compiled (and managed) code.

It was then stated that this advantage only applies to IE because IE interprets Javascript which is inefficient when compared to that of other browsers such as Chrome and FireFox which compile Javascript to machine code before execution and as such perform as well as Silverlight.

Does anybody have a definitive answer to this performance question. i.e. Do/will Silverlight and Javascript have comparable performance on Chrome and Firefox?

Answer 1

Speculating is fun. Or we could actually try a test or two...

That Silverlight vs. Javascript chess sample has been updated for Silverlight 2. When I run it, C# averages 420,000 nodes per second vs. Javascript at 23,000 nodes per second. I'm running the dev branch of Google Chrome (v. 0.4.154.25). That's still almost an 18x speed advantage for Silverlight.

Primes calculation shows a 3x advantage for Silverlight: calculating 1,000,000 primes in Javascript takes 3.7 seconds, in Silverlight takes 1.2 seconds.

So I think that for calculation, there's still a pretty strong advantage for Silverlight, and my gut feel is that it's likely to stay that way. Both sides will continue to optimize, but there are some limits to what you can optimize in a dynamic language.

Silverlight doesn't (yet) have an advantage when it comes to animation. For instance, the Bubblemark test shows Javascript running at 170 fps, and Silverlight running at 100 fps. I think we can expect to see that change when Silverlight 3 comes out, since it will include GPU support.

Answer 2

Javascript is ran in a virtual machine by most browsers. However, Javascript is still a funky language, and even a "fast" virtual machine like V8 is incredibly slow by modern standards.

I'd expect the CLR to be faster.