Memory test - Firefox vs Firefox 3.0 b 1

Memory test - Firefox vs Firefox 3.0 b 1

Summary: Does Firefox 3.0 beta 1 do a better job of handling memory than earlier versions? In a test put Firefox 3.0 beta up against Firefox in a series of tests.

TOPICS: Hardware, Browser

Does Firefox 3.0 beta 1 do a better job of handling memory than earlier versions?  In a test put Firefox 3.0 beta up against Firefox in a series of tests.

Before I go any further, a few disclaimers and notes.  First off, I've carried out this test on a single system running Windows Vista Home Premium on which Firefox had not been previously installed.  The system has 2GB of RAM.  Both Firefox and Firefox 3.0 b 1 were installed fresh using a standard install.  For each test I visited the same web pages and did my best to make the browsing the same on both versions.

OK, with that out of the way, on with the tests.  I simulated three different browsing scenarios:

  • Loading a five pages into the browser
  • Loading a single page and leaving the browser for 10 minutes
  • Loading 12 pages into the browser and wait 5 minutes

Here are the results:


  • The memory test - Firefox vs Firefox 3.0 b 1Loading a five pages into the browser - 35,640KB (img)
  • Loading a single page and leaving the browser for 10 minutes - 47,852KB (img)
  • Loading 12 pages into the browser and wait 5 minutes - 103,180KB (img)

Firefox 3.0 b 1

  • Loading a five pages into the browser - 38,644KB (img)
  • Loading a single page and leaving the browser for 10 minutes - 63,764KB (img)
  • Loading 12 pages into the browser and wait 5 minutes - 62,312KB (img)

Check out the complete screenshot gallery.

Just to give us a baseline, I repeated the 12 page test using Internet Explorer 7 and found that the browser used 89,756KB (img), more than Firefox 3.0 beta 1 but substantially less than Firefox

This is interesting.  Initially it seemed that Firefox 3.0 beta 1 was consuming more memory than, but during the twelve page test I started seeing what I've been seeing before - spiraling memory consumption when the browser is under significant load.  I'm certain that if the browser had been left open longer, memory usage would have continued to rise.  I didn't see much signs of Firefox 3.0 beta 1 doing this.  Certainly based on this test and from using Firefox 3.0 beta 1 today, I do think that things have significantly improved.

Anyone else taken Firefox 3.0 beta 1 for a spin?  Any thoughts, feelings or observations?

Topics: Hardware, Browser

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  • 500MB of RAM on a regular basis?

    I'd be interested to see evidence of Firefox "consuming 500MB of RAM on a regular basis" as claimed in the "First look at Firefox 3.0 Beta 1" story.

    "...but during the twelve page test I started seeing what I?ve been seeing before - spiraling memory consumption when the browser is under significant load."

    100MB is hardly "spiralling memory consumption": especially with 2GB RAM.

    The problems with Firefox seem to arise with multiple tabs open (possible a lot of browsing history in each tab?) and the browser open for many hours.

    Any chance of seeing the result of a test comparing various browsers under these conditions? I'd be very interested to see the "spiralling memory consumption" actually documented. Whenever I try such a test, memory seems to max out at about 100MB on 1G RAM XP.
    • I just don't get it...

      I've got five tabs open right now in Firefox 2.0.9 and it's using 49Mb. I NEVER see all this out of control Firefox memory usage that I hear about.

      Maybe it's because I'm using noscript and adblock to filter out all the garbage.
      • Turn on JavaScript to see the memory issue

        JS intense pages are what crank the memory out of control in Firefox on my XP Pro boxes. If you have JS disabled, it's no wonder your memory doesn't go above 49MB.

        BTW: you're missing half the web if you're not running JavaScript. Try being not so paranoid.
        • How are we missing

          half the web? Maybe we just want to read the content without being annoyed by all the flashing blinking bauble ads that are ever present?

          I know personally I prefer clean and simple. Time is precious and I want to access the content I am after without all the silly bells and whistles.

          Guess I am old fashioned. But sometimes simple is better. ]:)
          Linux User 147560
          • What a curmudgeon...

            Your life is too busy and, um, precious, for the enriched content of js? Puleeze. Lighten up, Clarence...
            Michael Of Atlanta
          • Yes it is and

            the definition of enriched is dependent upon ones point of view. If I don't have a need for it or want it, then how is it enrichening?

            And who is Clarence? ]:)
            Linux User 147560
          • correct spelling is

            CARMAGEDDON HIGH OCTANE with expansion disc was neat add on but it had a tough downfall. If you owned Splat pack the expansion you still required the orginal Carmageddon compact disc (cds now a days)during install. So if you own both it worked well on Vista in command ....I wanna know where does one post the games that do function correctly for vista globally?
            Your Welcome I was wondering if anyone still knew that classic
            Go Thrill Kill PS1 hard and rare to find Thanks to EA
            theirs my props to ya. CNC all over the world challenge issued to me please I would enjoy gaining my cnc skills up in multi-player if EA could help me tonight I'll join a ladder again see you out there
          • Wha?

            re: spelling-- guess again, or look it up. No one is talking about games here. Start a new thread somewhere, here or at GameSpy or another Cnet network or whatever.

            Sounds interesting, though.
          • JavaScript is much more than just "flashing blinking bauble ads."

            JavaScript is the &lduqo;J” in “A[b]J[/b]AX” (Asynchronous
            [b]Javascruot[/b] And XML), [i]the[/i] main technology behind Web 2.0 that enables
            a Web page to act like a full desktop application, updating its data from the server
            without needing a full page refresh. Most AJAX pages are smart enough to
            "gracefully" degrade to performing full page refreshes on browsers with insufficient
            JavaScript support, or that have it disabled. Full page refreshes are alway slower,
            and usually [i]much[/i] slower, and more distracting, than AJAX partial refreshes.
            Popular AJAX sites include GMail, YouTube (notice how you can page through the
            Text Comments and even post a Text Reply, while the video is playing, without
            disrupting the video? Not if you have JavaScript disabled, you can’t!
            That’s AJAX at work!), TV Guide Listings (so you can hover over a show in
            the grid to see its summary pop up — without AJAX, it would have to
            download the summary for every show in the grid, for all several hundred channels
            you might have in a major market cable system or any satellite system, before
            displaying any of them), search engine, and many, many more.

            Javascript is also needed by all ASP.NET web sites (any site with pages that end in
            “.aspx” instead of “.htm” or “.html” or
            &ldquo.asp”) to enable postbacks, which are mandatory for proper
            operation. Most shopping carts depend on it for calculation of the subtotals,
            without needing to perform a server refresh. Many Web forms use it for client-side
            validation, to warn you of missing required fields, improperly formatted data, mis-
            matched password and confirmation, etc. before wasting the time to submit to the
            server, usually using instant error message pop-ups. With JavaScript disabled, most
            such pages will automatically degrade to server-side validation, which means you
            have to wait until the page gets submitted and the error messages returned back to
            you during a full page refresh to even know that you made a mistake. Some
            amateur web sites may rely on JavaScript-based client-side validation without
            backing it up with server-side validation, which is very dangerous and would
            enable incomplete and/or improper data to be submitted and accepted (if you are a
            Web developer, never, [i]ever[/i] do this!).

            JavaScript is also used for basic navigation in many sites. Sites with drop-down
            menus or tree menus may not work without JavaScript (especially, in the former
            case, with Win IE6, which lacks the alternative ability to do drop-down menus using
            CSS 2.1 — Gecko [FF], Opera, Safari, Konquerer, and Win IE7 can all do that).

            In short, even sites which appear to work without JavaScript often work much better
            with it enabled.

            That said, there are exploits to JavaScript, and it can be dangerous in the hands of
            a malware writer. The more power that exists in any system, the more it can be
            misused, and JavaScript adds substantial power to the Web experience.

            The [i]NoScript[/i] extension is good protection, but do enable JavaScript for sites
            that you trust and frequent often. And, since one of the main memory leaks in FF2
            seems to be in its JavaScript implementation, using [i]NoScript[/i] does mitigate the
            memory leaks problem drastically by reducing the use of the JavaScript engine. Not
            because of blocking ads per se, but because the JavaScript interpreter itself is
            buggy in terms of memory leaks.
            Joel R
          • After reading through your long

            and ill formatted diatribe your conclusion is simple and correct. I use no script for the security layer is ads as well as assisting to keep web pages cleaner.

            If I go to a web site that I need to use a form then I will enable just that web site via no script. As an example, ZDNet has at some times up to 8 or more elements that utilize javascript, and yet I find that in order to post and browse, I only need to enable 1 of them. The others are generally items I have no need for or do not want to participate in, such as google-analytics.

            I also use ad-block and flash-block to "clean up" web pages so that I get only the content I want without being annoyed. ]:)
            Linux User 147560
          • Agree totally...

            ...he was basically implying "you can have your cake and eat it."

            "... That said, there are exploits to JavaScript, and it can be dangerous in the hands of a malware writer. The more power that exists in any system, the more it can be misused, and JavaScript adds substantial power to the Web experience."

            Ahhh, phooeee!

            He *arbitrarily contradicts* his own assertions in the same breath and then expects (with audacity mind you) the rest of us to buy into his convoluted logic?

            Javascript may be all he's *marketing* it as - but if it wasn't hooked so gardamned tightly into the dynamics of most web browsers, i'd be rid of it faster then you could say "malware loves Java".

            The bottom line is, all its well documented vulnerabilities to remote execution (and the like) are the very reason many users just disable javascript. If he managed to focus objectively, he would have realised why it is a *damnable yoke* that end users have been lumped with for way too long a time. But then when you work as in online advertising maybe you start believing in all the hype and trash ... ;^}

            "You can fool some of the peolple some of the time - but not all of the people all of the time."
          • fair points, but

            What about all the people who have no use for "Web 2.0", shopping, or most advertising? You can always enable js (and others) on a per-site or per-session basis.

            Just a note, since we are wandering a bit off the topic of memory handling at this point (since crossing the js enabled/disabled for benchmarks comments).

            have a good one :)
          • JavaScript

          • Well written

            But AJAX is only really a buzz word. Real people call it AJAX programs Javascript Applications or programs.

            Or at least, people who don't feel the need to put buxxwords on everything to make them exciting.
          • Correct, at least in theory, and perhaps for online shopping addicts.

            Correct, at least in theory, for only a small percentage of the average user's Web experience--most of us aren't shopping addicts.

            My normal experience of the Web is Java-free; I turn Java on in only those few cases where that dreaded code has been made mandatory by Web site control freaks and those with a paucity of imagination to program in a better way.

            It's about time that people who are in the know--and you're obviously one of them--started to campaign for a rationalisation of that shambles which goes under the general title of Web scripting--it's an unholy mess, the absolute anthesis of what ought to be a set of cohesive Web standards.

            (BTW, as a person who has been on line since the early days of ARPANET, it is my experience that the more scripting--Java, et al, that a site uses--the less the relevant content. Of course there are exceptions, but I've thousands of instances of where Web sites that do not use scripting--or use it most sparingly--have the most detailed or concentrated content. Most of the Web's scripting is taken up with forcing users to read trashy ads or pressing users to act in ways Web site developers want rather than the way users would instinctively prefer to act.)
          • 'Javaites' suffer from baubles bangles and bead deprivation & withdrawal.

            Right! I too was educated with books and not TV and videos--trained to concentrate at least long enough to comprehend a compound sentence.

            A common affliction of 'Javaites' is to suffer baubles bangles and bead deprivation [aka rich content withdrawal symptoms]. Unless their screens are polluted with visual noise and plethora of useless jiggering bouncing detritus they'll nuke the Web site within milliseconds.

            So mesmerised by colourful menageries of meaningless moving distractions, they fail to realise that turning off Java will often more than double Web page access speed not to menton the improvement in their comprehension of the relevant content.

            One really has to feel some sympathy and compassion for these poor unfortunates.
        • Be paranoid

          Douglas Crockford, who is no less than senior Javascript Architect at Yahoo and inventor of JSON, advises everyone to be paranoid, use [i]Noscript[/i] with Firefox, and block untrusted Javascript scripts. See his blog article at

          • I second the use of NoScript

            I've used it for some time now, and I've been very happy with it. And, if one is unsure about a site, there is even the option to temporarily allow scripts from specific (listed for you, in fact) sites - so you can see what web content you might be missing.
          • no script

            Greatest invention since the wheel. Doubly important, make that octal-ly important for windows users.
          • Be Paranoid: So am I

            I also run with 'No Script' enabled along with 'Ad Blocker Plus'. I must have 70 sites [b]completely[/b] blocked. (e.g. Double-click, Adsonar, Akami, etc). I do not want their crap on my system. If I encounter a site that I do visit on a regular basis, it goes in my 'white list'. And as another poster mentioned, you can [u]temporarily allow[/u] a script to be run. Simply put, [i]I will not allow untrusted Javascript applications to run on [b]my[/b] machine!!!!![/i]