Comment Feed for Channel 9 - Inside IE 9’s High Performance JavaScript Engine http://ecn.channel9.msdn.com/o9/previewImages/100/542445_100x75.jpg Channel 9 - Inside IE 9’s High Performance JavaScript Engine The IE9 Platform Preview includes the first release of the new JavaScript engine. This new engine compiles JavaScript source code into high-quality native machine code. It also has a new fast interpreter for sequentially executing script on traditional web pages and contains several improvements to the JavaScript runtime (including improvements in type representation, polymorphic inline caching and efficient implementation of machine types). IE 9's JS engine employs a dual execution pipeline architecture which enables very efficient interpreting of JS code while at the same time compiling JS code in the background (on a different thread), taking advantage of the processing power of modern hardware.In terms of code analysis, IE 9's JS engine analyzes hot functions and puts them into a queue for background compilation. There are other types of analysis that happen (or could happen). For example, the ability to change execution strategies based on power state (if a PC is on battery power, for example, then limit the amount of codegen). In this episode of Going Deep, we meet the leaders of the team that builds this new high performance JavaScript engine: GM Shanku Niyogi, Architect Steve Lucco and GPM John Montgomery. If you're interested in how IE 9's JavaScript engine works, then you'll certainly enjoy this great conversation.Tune in. Enjoy. en Thu, 23 May 2013 14:20:42 GMT Thu, 23 May 2013 14:20:42 GMT Rev9 Re: Inside IE 9’s High Performance JavaScript Engine I can haz a cat IE9? Smiley Excellent, I remember back in the day I actually had to re-architecture my JavaScript code to make it work smoothly with IE6 (it worked fine on Opera and Firefox).

posted by Ion Todirel

]]> http://channel9.msdn.com/Shows/Going+Deep/Inside-IE-9s-High-Performance-JavaScript-Engine#c634064027520000000 Fri, 09 Apr 2010 09:39:12 GMT http://channel9.msdn.com/Shows/Going+Deep/Inside-IE-9s-High-Performance-JavaScript-Engine#c634064027520000000 Ion Todirel Re: Inside IE 9’s High Performance JavaScript Engine Charles, next time you meet them can you ask them why they do not cache the native code once the JS method has been codegen'ed and run the cached code for future visits to the site, as long as the method stays the same?

posted by soum

]]> http://channel9.msdn.com/Shows/Going+Deep/Inside-IE-9s-High-Performance-JavaScript-Engine#c634064122080000000 Fri, 09 Apr 2010 12:16:48 GMT http://channel9.msdn.com/Shows/Going+Deep/Inside-IE-9s-High-Performance-JavaScript-Engine#c634064122080000000 soum Re: Inside IE 9’s High Performance JavaScript Engine Yes, I can Smiley

 

It's a very interesting case. It's also a harder problem to solve (on various levels) than it may appear to be on the surface (just cache compiled code and then run it on subsequent visits to the site is not an effective or safe approach). That said, I am not a JS engine developer. Next time I visit them, I'll be sure to ask about this.


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posted by Charles

]]> http://channel9.msdn.com/Shows/Going+Deep/Inside-IE-9s-High-Performance-JavaScript-Engine#c634064343830000000 Fri, 09 Apr 2010 18:26:23 GMT http://channel9.msdn.com/Shows/Going+Deep/Inside-IE-9s-High-Performance-JavaScript-Engine#c634064343830000000 Charles Re: Inside IE 9’s High Performance JavaScript Engine Thanks for this Smiley

 

I love the idea of both background compilation and background garbage collection.

 

It'll be interesting to see what kinds of applications Chakra and other IE 9 creatures will enable.

posted by exoteric

]]> http://channel9.msdn.com/Shows/Going+Deep/Inside-IE-9s-High-Performance-JavaScript-Engine#c634064416290000000 Fri, 09 Apr 2010 20:27:09 GMT http://channel9.msdn.com/Shows/Going+Deep/Inside-IE-9s-High-Performance-JavaScript-Engine#c634064416290000000 exoteric Re: Inside IE 9’s High Performance JavaScript Engine We didn't talk about Background GC for JS... Smiley You are referring to that mechanism in CLR4, I assume...

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posted by Charles

]]> http://channel9.msdn.com/Shows/Going+Deep/Inside-IE-9s-High-Performance-JavaScript-Engine#c634064524720000000 Fri, 09 Apr 2010 23:27:52 GMT http://channel9.msdn.com/Shows/Going+Deep/Inside-IE-9s-High-Performance-JavaScript-Engine#c634064524720000000 Charles Re: Inside IE 9’s High Performance JavaScript Engine Charles,

I realise I may be late and offtopic, however, just want to say the  WMV(High) version is Excellent- Unreal infact. By the way what are the camera’s you guys use?

posted by CaptainOblivious

]]> http://channel9.msdn.com/Shows/Going+Deep/Inside-IE-9s-High-Performance-JavaScript-Engine#c634064886770000000 Sat, 10 Apr 2010 09:31:17 GMT http://channel9.msdn.com/Shows/Going+Deep/Inside-IE-9s-High-Performance-JavaScript-Engine#c634064886770000000 CaptainOblivious Re: Inside IE 9’s High Performance JavaScript Engine I know stating the entire semantics of caching compiled JS in a single line is oversimplification, but I ain't a JS engine developer either. So, let's hear it from those who are themselves.

posted by soum

]]> http://channel9.msdn.com/Shows/Going+Deep/Inside-IE-9s-High-Performance-JavaScript-Engine#c634064971670000000 Sat, 10 Apr 2010 11:52:47 GMT http://channel9.msdn.com/Shows/Going+Deep/Inside-IE-9s-High-Performance-JavaScript-Engine#c634064971670000000 soum Re: Inside IE 9’s High Performance JavaScript Engine Yep, I'm just merging the ideas in my head which they appear to be completely orthogonal. I don't know how parallelizable compilation and garbage collection is but even just background compilation and collection is a bit of a dream; I think the first time I read about parallel garbage collection was in Object Oriented Software Construction (OOSC) by Bertrand Meyer (could be mistaken), where the notion of a parallel garbage collection is introduced, I think it even mentioned it as taking place on a separate CPU (same die or not).

posted by exoteric

]]> http://channel9.msdn.com/Shows/Going+Deep/Inside-IE-9s-High-Performance-JavaScript-Engine#c634065002430000000 Sat, 10 Apr 2010 12:44:03 GMT http://channel9.msdn.com/Shows/Going+Deep/Inside-IE-9s-High-Performance-JavaScript-Engine#c634065002430000000 exoteric Re: Inside IE 9’s High Performance JavaScript Engine We used a really nice camera (not sure of the exact model). Michael O'Neill, our awesome videographer/director/producer, flmed this. He's a pro!


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posted by Charles

]]> http://channel9.msdn.com/Shows/Going+Deep/Inside-IE-9s-High-Performance-JavaScript-Engine#c634065153950000000 Sat, 10 Apr 2010 16:56:35 GMT http://channel9.msdn.com/Shows/Going+Deep/Inside-IE-9s-High-Performance-JavaScript-Engine#c634065153950000000 Charles Re: Inside IE 9’s High Performance JavaScript Engine CLR4, shipping with VS2010, employs a background GC. Learn about it here: http://channel9.msdn.com/shows/Going+Deep/Maoni-Stephens-and-Andrew-Pardoe-CLR-4-Inside-Background-GC/

 

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posted by Charles

]]> http://channel9.msdn.com/Shows/Going+Deep/Inside-IE-9s-High-Performance-JavaScript-Engine#c634065154910000000 Sat, 10 Apr 2010 16:58:11 GMT http://channel9.msdn.com/Shows/Going+Deep/Inside-IE-9s-High-Performance-JavaScript-Engine#c634065154910000000 Charles Re: Inside IE 9’s High Performance JavaScript Engine We will Smiley

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posted by Charles

]]> http://channel9.msdn.com/Shows/Going+Deep/Inside-IE-9s-High-Performance-JavaScript-Engine#c634065155320000000 Sat, 10 Apr 2010 16:58:52 GMT http://channel9.msdn.com/Shows/Going+Deep/Inside-IE-9s-High-Performance-JavaScript-Engine#c634065155320000000 Charles Re: Inside IE 9’s High Performance JavaScript Engine "For example, the ability to change execution strategies based on power state (if a PC is on battery power, for example, then limit the amount of codegen)."  ... I believe this is mentioned in the video as well...

 

And then you guys talked about how it's bad to let the developer give 'hints' how to run the code [generally I agree], so I'll assume there is no "disregard power state flag"...  I can just imagine someday, somewhere, people are going to hit a bug where someone complains "the website seems slow on my browser but only on my laptop and only on my commute to work".

 

Honestly, I dislike the idea of VM logic changes based on state (such as current load or power state) for anything but garbage collection

 

Just get it right Smiley

posted by deedubb

]]> http://channel9.msdn.com/Shows/Going+Deep/Inside-IE-9s-High-Performance-JavaScript-Engine#c634066390720000000 Mon, 12 Apr 2010 03:17:52 GMT http://channel9.msdn.com/Shows/Going+Deep/Inside-IE-9s-High-Performance-JavaScript-Engine#c634066390720000000 deedubb Re: Inside IE 9’s High Performance JavaScript Engine Does the JS engine come as a library that can be reused in other apps apart from IE9, similar to V8?

posted by boroleprashant

]]> http://channel9.msdn.com/Shows/Going+Deep/Inside-IE-9s-High-Performance-JavaScript-Engine#c634270679330000000 Sat, 04 Dec 2010 13:58:53 GMT http://channel9.msdn.com/Shows/Going+Deep/Inside-IE-9s-High-Performance-JavaScript-Engine#c634270679330000000 boroleprashant