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Firefox 4 is unusable due to excessive Memory usage - when is the fix?

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There are just so many people complaining about Firefox 4 - all with the same basic problem - Firefox 4 consumes far-too much memory and appears to increase memory usage over time.

So far I have heard NOTHING from Mozilla regarding this problem.

Have Mozilla identified the problem? Is there a work around? When will there be a permanent fix?

Modified by IanSeale

All Replies (20)

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John99 "I just stumbled across a thread and a blog: solved-firefox-freezes-every-10-seconds that you may find of interest".

That link refers to Firefox 3.6.13 - NOT Firefox 4 - remember the posters here are all saying they are having problems with Firefox 4 that they didn't have with previous versions.

I do thank you though for the Bugzilla link. It does show that some people are on to the source of the problem with Firefox 4, even if it is incredibly detailed. I'm sure a lot of us posting here have varying levels of technical knowledge, but few are software developers. Like I said in my topic title - when is the fix? We're just users here, all we want is a fix.

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Hi Ian,

___ "That link refers to Firefox 3.6.13 - NOT Firefox 4" ___

I addressed my comment contianing that link to IslanderCirqe because of

  • mention of sessionstore files being deleted in both IslanderCirqe's & Helgie Klien's solutions to a problem
  • The meta listing of bugs seemed more useful than the search IC had already found.

___ "Like I said in my topic title - when is the fix? "___

I think the problem is that all the big and common problems are found and fixed. What remain are problems that are less common, and are often down to interaction with other software. There is imo unlikely to be any single fix, or any single problem.

Many users presumably just do not see any problem at all. I am using firefox on a couple of legacy computers with low RAM but am not really seeing any problems.

Some bugs/problems are so serious they break firefox, and it will not work at all, others go almost unoticed either they have only a minor effect, or occur only in very specific circumstances.

___ "We're just users here, all we want is a fix. "___

What happens is

  1. someone has a problem, details are obtained of that problem,
  2. a bug is filed, giving
    1. a good description of the problem,
    2. details of steps to reproduce the problem
    3. if it is due to a change in firefox, then the nightly change on which this first occurs is identified
  3. the bug gets comfirmed (or not) ie others check it happens as expected
  4. the techies prioritise the importance of the bug, obtain more info if necessary and try to take steps to fix it, or otherwise resolve the issue.

Remember the numbers of Firefox users will be in the hundreds of millions, there will be all sorts of possible combinations of hardware software, and configuration changes and use patterns that need to be considered. The amazing thing is that Firefox mostly works, and works well in such an environment. NB

If you have the time to playaround with your FireFox settup, and do some troubleshooting possibly we could find more about what is causing your specific problem. Your problem may relate to an alreasy filed bug, it may be new, or it may be something with an already known solution.

Another comment that may be of use to those looking at this thread, firefox has had an about:cache and from I think version 3.6 now has an about:memory, it is a report that is not available from the standard menus. Some technically minded persons may find the info useful, key about:memory into the location bar.

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I have a similar problem. I run a 6-core, 12GB RAM Windows 7 Ultimate x64 machine. I didn't notice the memory leak until Firefox repeatedly crashed on me. I checked the memory usage and it was spiking over 1GB. Clearly, this isn't normal. Memory usage should not continue to clime after you stop opening new tabs. It used to hover around 240MB with my usual amount of tabs.

I tried something suggested in another forum post: opening a blank tab and refreshing it when the memory usage started spiking. It seems to help, but that's just a workaround. This issue should be fixed more permanently.

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Hi lywellyn,

It is always a good idea to start a new thread/question for each problem, even when they are apparently similar, so I suggest you do that with your own problem. By all means provide links between the two threads, but I suggest you please start your own question with your own details and system etc. info.

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You just don't get it, do you? "There are just so many people complaining about Firefox 4 - all with the same basic problem - Firefox 4 consumes far-too much memory and appears to increase memory usage over time". That was my original post, and I see no reason to change it.

These people have not changed hardware or software, have not changed the way they work, and are not running any complex or unusual applications - or putting any other demand on Firefox 4 that they didn't apply to Firefox 3.6.16.

The common compliant is that the "excessive Memory usage" problem did not occur on previous versions of Firefox and has only occurred since using (or trying to use) Firefox 4 - not one is posting here for fun or to give Mozilla a kicking - largely, posters are pro-Mozilla and feel let down. They will also be driven away to another browser until such time as someone comes on here, owns up to the problem, and communicates what the fix is and when, and how, it will be implemented.

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Please then prove that it is a regression problem.

Show the problem occurs in firefox 4 but not in firefox 3.6

Give concrete examples of what is occurring.

imo it is pointless just to make suggestions there are problems with
so many people complaining about Firefox 4 - all with the same basic problem

Why not just step up to the mark and use your own examples, but give the important detail required, and controlled & reproducible examples. Demonstrate a problem that someone can investigate.

Instead of asking me to shut up, please provide the information needed to corroborate and investigate the problems. You are on a support forum that is intended to investigate and solve Firefox problems you are not on a feedback site (I have already given a link for feedback).

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I've had the excessive memory problem since version 3 so the problem is not new to version 4. When it happens I just shut down firefox and restart it. If it happens in version 4 I will try to keep a log of what I was doing just before it started to leak memory.

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"Instead of asking me to shut up"

I've not once asked you to shut up - please don't say I did - you are making that up and that is slander. BTW nice response for a support forum.

The clue to the problem with Firefox 4 is in my original posting:

"Firefox 4 is unusable due to excessive Memory usage - when is the fix?

There are just so many people complaining about Firefox 4 - all with the same basic problem - Firefox 4 consumes far-too much memory and appears to increase memory usage over time.

So far I have heard NOTHING from Mozilla regarding this problem.

Have Mozilla identified the problem? Is there a work around? When will there be a permanent fix? "

I am expecting a response from Mozilla on this forum not people who get piqued and make up things that people have 'supposed' to have said - Apologise!

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Sorry Ian, you only said I was blinkered and you would rather I did not help, it was an adjacent post in this thread where someone suggested I shut up.

You are unlikely to get any response from Mozilla on this site, it is a community run support site. As I explained upthread much of the identification of problems is also by ordinary users, and for that matter a lot of the fixing and development is again by unpaid volunteers.

If you are asserting that the memory problem is a single simple problem then you will probably be incorrect. Again as explained previously bugs are tracked on bugzilla one of my recent posts showing a link to the list of memory problems that have been reported. Mozilla staff use and monitor bugzilla.

If you can show there is some other unreported reproducible problem you, or anyone else, may file a bug for that issue to be investigated; but it will not be helpful to file a bug saying a web search shows there is a problem. A bug to be investigated need full details of the specific problem.

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Hi John99 Thanks for the links. I'm planning to gradually & systematically work through everything I can find to improve FF's performance, though it's tolerable as is. I have just discovered something else - I have my add-ons & plug-ins set to update automatically, plus while working through this issue have used the Add-ons Manager to double check that everything is updated. I thought everything was fine until I came across a reference to this: Lo & behold it reports that some of my plugins are outdated. Given that I just had a runaway memory incident (though FF only hung for 2-3 minutes) after playing a few YouTube videos, I'm hoping the updates will sort that out.

It appears that the automatic updates may not be working correctly.

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"It appears that the automatic updates may not be working correctly. "

That is a different subject from the main point of this thread. I have always suspected since its introduction that the update add-ons may not always work well however you are mentioning the Update Plug-ins I do not think am not sure Firefox makes any claims to check and update them.

The two main KB articles

  1. Use plugins to play audio, video, games and more
  2. Troubleshoot issues with plugins like Flash or Java to fix common Firefox problems

both link to the page you found Mozilla Firefox Plugin Check

Maybe Firefox does have some plugin update check facilities.

I note for instance toggling the pref plugins.update.notifyUser;false to true leads to Firefox starting on the Plugin Check page.

Modified by John99

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I've filed a Bug Report - but it looks like the excessive memory usage problem has been known for some time, and still unresolved.

Nicholas Nethercote [:njn] 2011-03-09 20:23:49 PST

This is a follow-on bug from bug 598466 (and bug 615199, which blocked it), which covered various memory size reductions and problems in Firefox 4. The following as-yet-unresolved bugs were carried over from that bug: bug 618031, bug 632012, bug 629601, bug 630447, bug 630738, bug 631045.

Note that this bug is intended to be about slimming down memory usage, eg. reducing the size of data structures. It's not about leaks and quasi-leaks; bug 640452 is tracking those.

Comment 1 The 8472 2011-03-09 22:45:12 PST

Do we have a bug for better accounting in about:memory? My current session uses 960MB private bytes, but the various allocation pools only account for about 200MB. If we could get a larger coverage it would make it easier to pin down where we can get the most savings.

Comment 2 Nicholas Nethercote [:njn] 2011-03-10 01:06:06 PST

(In reply to comment #1) > Do we have a bug for better accounting in about:memory?

Bug 633653.

Comment 3 Ed Morley [:edmorley] 2011-03-10 04:54:50 PST

I feel that it would be useful to have a bug along the lines of:

"Investigate why automated testing did not detect a 200-250% increase in per tab memory usage between 3.6.12 and Fx 4b4 / fill any gaps in testing"

(ie: why all the regressions from bug 598466 managed to slip past and making sure it doesn't happen again)

Is there one already for this?

Comment 4 DB Cooper 2011-03-23 12:44:06 PDT

Bug 643651 is a good (extreme) example of FF4's comparatively large memory use on image heavy pages (~1.5GB in this example, with peak memory > 2GB). Should it be added to this meta bug?

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Your newBug657232 Firefox 4 consumes far-too much memory and appears to increase memory usage over time.

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Hi John I tried a possibly cause of the error, and there are no problems now... What did I do? One of the tabs was Vimeo. I closed the tab, and no problems after that. I had previously looked at one of the videos there, so I think that is the best seed I can give you to find the error. PC has been left powered during the week end, and no memory problems this morning. PC is updated with all the latest patches from software vendors (Microsoft, Adobe, Java)

brg Øystein Bach

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Hi Øystein,

Glad to hear you seem to have solved your problem.

If you wish to have that investigated further then if you find opening Vimeo, again produces a problem that goes away again after you close the Vimeo tab please post back and start a new thread, (post a link to the new thread) we can then consider whether there is something odd about that site or leaving some videos open.

Admittedly there will be some changes in firefox that could be made to alleviate some problems As I have been saying in this thread there are probably a lot of causes of memory problems rather than just one problem.

Keeping a lot of tabs open will be likely to cause Firefox to slow down and use more memory, and I know developers have been running tests for instance with 80 and 300 tabs open with the intention of seeing what can be done to minimise problems with Firefox's memory utilisation, and are also considering new user interface reporting/diagnostic tools.

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Can I add some comments here....

I have been using FF4 for about 4 weeks now and have none of the issues some of you are comlaining about. In fact I have done the opposite, I have come back to FF4 from Chrome.

I still do think it is as fast as Chrome, not by a long shot, but resource wise it is comparable. The thing I have issue with is I got use to some Apps with Chrome, if FF could use Apps like Chrome does - then we are in a whole new world :)

My only other gripe is the font rendering is not as good as Chrome or IE, actually it is the worst of all modern browsers, but I hope the devs are working on that fix.

So please do not generalise that FF4 is bad, many of us are happily using it and having no issues at all.

If you have an issue, going off at the Mozilla devs is NOT going to help you, calm, informed and detailed discussions will get you further and will most certainly get a better response from mozilla devs.

Cheeres all


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Bugzilla report:

Bug 640452 - (mlk-fx5+) [meta] leaks and quasi-leaks for Firefox 5+

There appear to be consecutive Bug Reports, and Unresolved Bug Reports relating to Memory Usage in FF 4 - and FF 5?

Of those that are complaining of similar problems with FF 4 - when there were none with FF 3.6.16 - no one is doing anything unusual or, more importantly, differently. The only commonality that I have found to date is that it affects users with older operating systems, which are likely to be older machines too. It is entirely possible that EVERYONE has the problem, but that is masked by newer, higher-spec'd machines and operating systems.

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Ian, I can't see any actual details of your excessive memory usage, available memory etc. We really need a lot more details of your set-up. I am one of these people with absolutely no memory problems with Fx4 - my Task Manager says 115 MB at the moment.

I would bet on Windows 2000 being your problem. Bare Firefox 4 is said to run O.K. in Win 2000 but every add-on is going to increase the load. I believe, for example, that the latest versions of Flash will not work with Win 2000.

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Hi Alan,

Firefox 3.6.17 memory usage with 4 tabs open is 146MB and stable. With Firefox 4 it just kept climbing. Yes, running an older machine and operating system is part of the reason the problem is so pronounced for me, but that should not explain the climbing memory usage in FF 4. I'm happy to remove Add-Ons, and I'll do that when I a forced to use FF4 unless a fix is found.

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If you try some of those ideas now and try to make a case with hard facts about your situation you may actually find a solution to your problem, and you may get your bug looked at and something investigated. At the very least someone else may be able to offer you helpful suggestions about your specific problem.

@ Alan_r & gwm_box

Thanks for the constructive comments.

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