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Firefox Mozilla Software Upgrades Technology News

Mozilla Unleashes JaegerMonkey Enabled Firefox 4 279

Posted by timothy
from the some-big-hype-to-live-up-to dept.
An anonymous reader writes "Mozilla has published the first Firefox 4 build that integrates a new JavaScript engine that aims to match the performance in IE9 and reduces the gap to Safari, Opera and Chrome. This is really the big news we have been waiting for all along with Firefox 4 and it appears that the JavaScript performance is pretty dramatic and seems to beat IE9 at least as far as ConceivablyTech shows. Good to see Mozilla back in the game." The Mozilla blog gives a good overview of the improvements this brings; Tom's Hardware also covers the release.
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Mozilla Unleashes JaegerMonkey Enabled Firefox 4

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  • by rsborg (111459) on Thursday September 09, 2010 @03:35PM (#33527108) Homepage

    Ironically, the primary site for which I really need a faster Javascript engine is Slashdot. For a heavily-commented article I switch to Chrome.

    Switch to old-style comments viewing system... I just get a dump of comments, nested appropriately. Makes for much nicer reading on a non-mobile device, albeit being a bit more bandwidth intensive initially.

  • Re:In a Beta? (Score:5, Informative)

    by The MAZZTer (911996) < minus threevowels> on Thursday September 09, 2010 @03:41PM (#33527172) Homepage
    It's my understanding that feature freeze is tomorrow.
  • by MrEricSir (398214) on Thursday September 09, 2010 @03:47PM (#33527240) Homepage

    And cheers to the release!

  • by Shikaku (1129753) on Thursday September 09, 2010 @03:48PM (#33527254)

    Install ad-block and noscript.

  • Compatibility (Score:4, Informative)

    by Anonymous Coward on Thursday September 09, 2010 @03:50PM (#33527274)

    Firefox lagged chrome mostly because firefox cares a LOT more about compatibility, and adding all this crazy JIT compiled JS stuff is hard when you're trying to support all the introspection features which people have been using in firefox.

  • by clone53421 (1310749) on Thursday September 09, 2010 @03:50PM (#33527282) Journal

    There is a option in the account settings to control how many comments are loaded. Mine loads 250 at a time.

  • by Teese (89081) <> on Thursday September 09, 2010 @04:03PM (#33527426)

    Ironically, the primary site for which I really need a faster Javascript engine is Slashdot. For a heavily-commented article I switch to Chrome.

    Is chrome the only broswer that has problems with the idle.slashdot comment thread. It anytime I try to open a closed comment, it refreshes the page and only gives me the comment, it doesn't expand the comment inline like it does in a normal comment thread. I've always been to lazy to try other broswers.

  • by radish (98371) on Thursday September 09, 2010 @04:09PM (#33527490) Homepage

    The linked article is about 4.0b6-pre which is the first version to include JaegerMonkey. The other two links are to articles about the public release of 4.0b5, which doesn't include JM (it's headline feature is really the DirectDraw support on Windows).

    4.06-pre isn't currently being pushed to regular beta testers AFAIK.

  • Re:Compatibility (Score:5, Informative)

    by Anonymous Coward on Thursday September 09, 2010 @04:25PM (#33527678)

    The reason for that is that Mozilla is honest. Unfortunately, honesty is rarely appreciated.

    Opera and Webkit just added little tricks to pass the ACID 3 tests. They don NOT really correctly support all the stuff that ACID 3 is testing.

    It's comparable with graphics drivers that include tricks to score higher in specific benchmarks, but do not really make the graphics card faster. It's simply cheating.

  • Re:Compatibility (Score:5, Informative)

    by Anonymous Coward on Thursday September 09, 2010 @04:37PM (#33527804)

    Focussing too much on the acid3 test, or any other scorecard list of features, is bad for Web Standards.

    You'll find that the Webkit developers have outright states that they have bare-minimum implementations for some standards just to pass the last few points of acid3 that isn't really usable. Hixie listed as one of his bullet points of lessons learned to focus more on useful web standards rather than just any old non-widely-implemented standard.

  • by MacTenchi (104785) on Thursday September 09, 2010 @04:37PM (#33527808)

    Agreed. They are working on multiprocess, it's called Electrolysis []. It's very quiet, so I imagine they're behind schedule. It's also my impression that it's a very small team.

  • by Anonymous Coward on Thursday September 09, 2010 @04:40PM (#33527832)

    What are you talking about? I've never had a problem with Firefox on AMD64, even with 32-bit support disabled in my kernel.

  • by Anonymous Coward on Thursday September 09, 2010 @04:41PM (#33527846)

    This is by design. The /. employees have been trying to kill idle ever since day 1 when the PHBs forced it upon them.

    The launch announcement was "from the do-not-read-the-idle-section dept." (

    Just look at the responses in this subthread from that discussion

    Taco _wants_ idle to suck as hard as possible, to retain the soul of /.

  • Re:In a Beta? (Score:3, Informative)

    by flimflammer (956759) on Thursday September 09, 2010 @04:46PM (#33527890)

    Like version numbers, alpha/beta/etc are subject to interpretation...

  • Re:Back in the game? (Score:3, Informative)

    by omni123 (1622083) on Thursday September 09, 2010 @05:26PM (#33528264) Homepage

    I wish I could mod this flamebait. The early preview speed tests for IE9 compete with Chrome very well.

  • Re:Back in the game? (Score:4, Informative)

    by Fnkmaster (89084) on Thursday September 09, 2010 @05:55PM (#33528524)

    According to [] they have come from being 2x-3x slower than Safari and Chrome a few months ago (v8/sunspider benchmarks) to being within a few percent to 25% of Safari and Chrome, depending on the benchmark.

    I think that's pretty impressive - it basically puts them in the right ball game now, and narrows the performance gap to the barely noticeable range for most practical purposes.

  • by flink (18449) on Thursday September 09, 2010 @06:48PM (#33529084)

    How exactly do you do that? I've tried turning on and off every god damn setting in the preferences pages, and the only thing that doesn't seem to change at all is how the comments are displayed.

    Go to [], and select "Slashdot Classic Discussion System", Display Mode=Nested, Sort=Highest First, and Threshold=1. Then go to [] and select "Use Classic Index".

    You'll now have good old classic /., the way God intended.

  • Re:Are We Fast Yet? (Score:4, Informative)

    by jesser (77961) on Thursday September 09, 2010 @06:55PM (#33529148) Homepage Journal

    The JaegerMonkey team understands why it's currently slower on 64-bit than on 32-bit. One reason is that the larger pointers on 64-bit systems don't play well with the value representation []. If that can be fixed, perhaps by using a different value representation in 64-bit versions, it might end up faster on 64-bit than on 32-bit.

    They're working on speeding up the 64-bit version. They have to, because of the plan to ship Firefox 4 as a 64-bit application for Mac OS X 10.6 ;)

    (Btw, shows speeds of naked JavaScript engines, which are usually slightly faster than JavaScript engines inside web browsers.)

  • by CAIMLAS (41445) on Thursday September 09, 2010 @09:22PM (#33530036) Homepage


    I have 8 cores. I open 5 tabs, creating 5 processes. One tab crashes. One process crashes. The remaining 4 remain as they are; usually, it's quite simple to regain the crashed page by loading it.

    With stock firefox, that usually means pulling each of those 5 pages out of history again, after restarting the whole browser.

    As far as "hanging one core and not the whole processor" you do realize that in a modern operating system, processes are not inextricably linked to a core? If your whole system locks due to the browser hanging, that's poor system design (Windows, Mac) or failing hardware.

  • Re:In a Beta? (Score:3, Informative)

    by LaRainette (1739938) on Friday September 10, 2010 @06:25AM (#33532328)
    This is the dumbest fucking idea I have ever heard....

    You do realize 10000 is actually much less informative than do you ?
    Let's see about that :

    A. 10000 : it gives us one, and only one piece of info, this is the 10,000th version of the software. That's all. It could be 10 major versions over 10 years or 1 major version corrected 9999 times in a month.
    You have NO idea what happened to this software !

    And that's from a professional point of view.
    But let's go a little further : what's the difference between v10,000 and v10,001 ? You don't have a fucking idea. It could be a typo or it could be a major release with tons of new features and the (yet) unfixed bugs that come with this.

    SO even from a consumers point of view it sucks, it's not easier or smarter and it certainly isn't more informative.
    From my understanding the usual consumer doesn't need to know, but he definitely will understand the difference between and say 2.X.XX.XXXX

    Anyway I'm tired and your argument sucked so bad that I'm not going to invest anymore time counter arguing.
  • by Anonymous Coward on Friday September 10, 2010 @06:47AM (#33532408)

    I'm pretty sure there's a name for this kind of argument, but it's basically a regular fallacy.

    Firefox JS performance has nothing to do with being open source. Javascript did not matter for a very long time, it was only used for seldom tiny effects. That's why Firefox JS engine was not super high performance (albeit still much faster than anyone elses at that time), because it would have been seen as totally overkill.

    Things have changed and Firefox JS is adapting. Since it's using an old codebase, it's not as quick (it took Apple quite some time to give birth to Nitro, and Google just plain bought V8 tech - as for IE9, we all know it took them time too, it's not yet there.)

    And that's all there is. So much for the anti open source FUD btw.

    Also, it pays to look at the development trends. In preparation for Firefox 4.0, Mozilla has been working to improve their tracing engine (called Spidermonkey I believe), and at the same time develop and then tune a JIT compiler. Mozilla has designed these efforts to be complementary, so that they could be merged to get the best of both approaches. The combined javascript engine has been dubbed JaegerMonkey.

    Mozilla development first merged these two different methods into the one engine only about two weeks ago, and now they are tuning it. Here is their record of how they have been going:

    The trend is very interesting, is it not? The very first test of the combined engine, JaegerMonkey, was between a 10% and 35% improvement, depending on the benchmark.

    If the trend holds true to form, JaegerMonkey will be the fastest javascript engine of all in somewhere between one and three weeks time.

    So much for the FUD that "FOSS always lags behind". Due to JaegerMonkey and hardware accelerated rendering, Firefox 4.0 has a decent shot at becoming once again the speed king of all browsers.

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