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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?

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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I am using MS XP home edition, and ever since I upgraded to FF 4.0, I have had this 100% memory usage problem, and have had my IE crash too. I also had the error messages RFC 5749 see 2009 - 3555 for my mail server at Suddenlink, and set the "security.ssl.allow_unrestricted_renego_everywhere__temporarily_available_pref " to False, as suggested, which seemed to fix that problem 'most' of the time, but the page still hangs up every so often and is always SLOW to load. I too am so frustrated that I am considering disconnecting service and going to the library to use their computers.

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If IE crashes too, I doubt if Firefox or the upgrade are your problem.

Strongly suggest you start a new thread.

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Ian Seale 2011-05-24 05:00:10 PDT

One final 'additional' before this one gets closed.

I upgraded to Firefox 5 on one of my laptops (the data above) and left the other one running 3.6.17 (they are both similar age, processor, memory and the same operating system).

With the same 3 tabs open on the same 3 websites Firefox 3.6.17 is running at a stable 130,000k memory. It fluctuates by about 5,000k, but that is it, no 'climbing' or 'climbing' and 're-setting' at all - just stays more-or-less the same. You can see how stable FF 3.6.17 is from the stats below:

12:44pm - Checking on 'Task Manager' memory usage is 130,008k. 12:46pm - Checking on 'Task Manager' memory usage is 130,324k. 12:47pm - Checking on 'Task Manager' memory usage is 130,984k. 12:48pm - Checking on 'Task Manager' memory usage is 131,024k. 12:49pm - Checking on 'Task Manager' memory usage is 131,952k. 12:50pm - Checking on 'Task Manager' memory usage is 130,028k. 12:54pm - Checking on 'Task Manager' memory usage is 133,836k. 12:56pm - Checking on 'Task Manager' memory usage is 134,672k.

So, even though Firefox 5 is miles better than Firefox 4 in its memory management/demand there is still something different in the build (from Firefox 3.6.17) that causes it to increase memory usage over time - even if it then re-sets as it 'dumps' garbage. So this might be the new 'normal', but it wasn't normal in FF 3.6.17.

FF 5 is good, but maybe there is something there that still needs a tweak to make it more stable (like FF 3.6.17).

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EDIT

I think many readers of this thread may find this blog of interest. Leak reports triage, May 24, 2011


I did try to explain up thread that, unfortunately these issues are rather complex, and further info is often needed in order to try to progress such matters. I am pleased to note you did make progress and post additional info in your bug ,thanks.

One other point you may or may not be aware of, it is possible to use more than one version of firefox:

Modified by John99

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My posting above (From my Bug report) looks confusing, as the detail of the Bug report that I refer to was pasted on this topic earlier this morning, but for some reason it's not there.

OK, so here's the Bug Report conversation that led up to, and including, my post (above) - Confusing? Sorry. But it should make more sense and tells you where to get Firefox 5 Beta too.

______________________________________________________

Nicholas Nethercote [:njn] 2011-05-24 00:48:36 PDT

Ian, we appreciate the report, but it's likely this bug will be closed because there are a number of prior bugs like this one. You'll be interested by http://blog.mozilla.com/nnethercote/2011/05/24/leak-reports-triage-may-24-2011-2/ This is an example of a bug I would classify as "[CLOSE?]" -- without specific steps to reproduce (eg. a specific website that triggers the problem) and some memory measurements, it's almost impossible for developers to do anything useful.

Having said that, Firefox 5 has fixed a number of leaks, which might be enough to get rid of the problem for you. Eg. see bug 640923 comment 27. It would be good to know if this helps you. You can get Firefox 5 betas at http://beta.mozilla.org. ______________________________________________________

Ian Seale 2011-05-24 01:42:50 PDT

Thanks for the information and help Nick.

I've just upgraded from Firefox 3.6.17 to Beta 5 and it at first appeared to be a lot more stable and responsive than Firefox 4.

Intitial memory usage (with 3 Tabs open - BBC News, BT Yahoo Mail and this one) was 142,000k and stable.

However, checking the memory usage 5 minutes in the usage was steadily climbing (as I was experiencing in FF 4) by 100k increments at every refresh. On this occasion (not like in FF 4 where it kept on climbing) memory usage levelled out at 170,000k and then fell back to under 150,000k but continued to climb but in much smaller increments (10k to 50k jumps).

Another 5 minutes in and memory usage was up to 160,000k - this is with absolutely nothing going on - and still continuing to climb - in the time it's taken to type this it has risen by 6,000k.

From memory, memory usage on Firefox 3.6.17 did vary between 90,000k and 120,000k but was stable.

9:32am - Checking back on Task Manager memory usage is now up to 170,000k.

Memory usage on Firefox 4 was higher, and climbed even higher, so by comparison, FF 5 looks better, but still has a problem - just less of one.

9:34am - Checking back on Task Manager memory usage is now up to 176,000k.

9:35am - Checking on Task Manager memory usage has dropped back to 124,000k.

9:37am - Checking on Task Manager memory usage is rising again to 130,000k.

OK - So this is a little weird - Firefox 5 seems to have the same memory climbing problem (but to less of an extent) - but 'tops out' at 170,000k-180,000k and 'resets' to around 120,000 - only to climb gradually again.

9:41am - Checking on Task Manager memory usage is rising again to 138,000k.

If Firefox 5 becomes unusable, I'll check memory to see if it's gone over 180,000k - but I suspect the cycle (above) will repeat itself - in which case the memory climbing will not be enough to affect functionality.

Once again, thanks for your help. ______________________________________________________

Nicholas Nethercote [:njn] 2011-05-24 02:38:19 PDT

Ian, where are you getting your measurements from?

You might like to try loading the page called "about:memory", which tells you various things about Firefox's memory usage. In Firefox 5 it's output isn't great, it'll be better in Firefox 6, but the breakdown might be informative. I would expect that the js/gc-heap is probably going up and down a lot. The up and downs you are seeing are to be expected, because garbage collection occurs periodically. Memory usage rising when nothing is happening is not necessarily unexpected either, because lots of websites continually do stuff even if you don't touch them.

Are you happy if I close this bug, based on (a) your improved results, and (b) the list of existing similar bugs we have about memory usage? ______________________________________________________

Ian Seale 2011-05-24 02:52:05 PDT

Hi Nick,

My measurements are taken from Windows Task Manager.

10:44am - Checking on 'Task Manager' memory usage is 175,000k. This is with 4 tabs open (BBC News, Facebook, BT Yahoo Mail, and this one).

Firefox 5 (Beta) is usable though, where Firefox 4 just plain wasn't - so I am pleased that Mozilla has identified and rectified the problem - and will win it's friends back.

10:49am - Checking on 'Task Manager' memory usage is 183,000k.

10:50am - Checking on 'Task Manager' memory usage is 142,000k.

So it appears Firefox 5 is 'dumping' garbage at around 185,000k memory.

Thank you for all your help. Please close this 'Bug' but please note that the fix was to upgrade to Firefox 5 Beta should anyone else be searching for a solution. ______________________________________________________

[reply] [-] Comment 12 Nicholas Nethercote [:njn] 2011-05-24 02:56:48 PDT

Thanks, Ian! ______________________________________________________

Ian Seale 2011-05-24 05:00:10 PDT

One final 'additional' before this one gets closed.

I upgraded to Firefox 5 on one of my laptops (the data above) and left the other one running 3.6.17 (they are both similar age, processor, memory and the same operating system).

With the same 3 tabs open on the same 3 websites Firefox 3.6.17 is running at a stable 130,000k memory. It fluctuates by about 5,000k, but that is it, no 'climbing' or 'climbing' and 're-setting' at all - just stays more-or-less the same. You can see how stable FF 3.6.17 is from the stats below:

12:44pm - Checking on 'Task Manager' memory usage is 130,008k.

12:46pm - Checking on 'Task Manager' memory usage is 130,324k.

12:47pm - Checking on 'Task Manager' memory usage is 130,984k.

12:48pm - Checking on 'Task Manager' memory usage is 131,024k.

12:49pm - Checking on 'Task Manager' memory usage is 131,952k.

12:50pm - Checking on 'Task Manager' memory usage is 130,028k.

12:54pm - Checking on 'Task Manager' memory usage is 133,836k.

12:56pm - Checking on 'Task Manager' memory usage is 134,672k.

So, even though Firefox 5 is miles better than Firefox 4 in its memory management/demand there is still something different in the build (from Firefox 3.6.17) that causes it to increase memory usage over time - even if it then re-sets as it 'dumps' garbage. So this might be the new 'normal', but it wasn't normal in FF 3.6.17.

FF 5 is good, but maybe there is something there that still needs a tweak to make it more stable (like FF 3.6.17). ______________________________________________________

Modified by IanSeale

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A separate subject entirely,

  • missing posts

but there have been at least a couple of instances, over recent hours, where I have thought I had posted and then not been able to find it. Not sure if its a wetware ! problem or a glitch with the sumo site. You are the only person I have noticed comment about this.

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@obach

I just want to add that I experience the exact same problem!! I have FF4 on my work PC (which is typically left on overnight) and when I came in this morning, FF was consuming approx 1.2 GB of RAM!! This caused my PC to become unusable due to an insane amount of page-swapping/hard disk activity and I had to kill the app, losing the pages I had open.

I find a restart of FF always results in normal memory usage again (~150 MB RAM) but, over time, this usage increases insidiously to the point where it impacts on system performance. And this it not just a FF4 issue, I noticed the same thing in each version of FF3.

I am really frustrated and fed up with this issue at this stage and, seeing that Mozilla still don't have a handle on this long-running problem (nor do they even acknowledge it!!), I think I'll be soon be ditching FF for Google's leaner browser Chrome.

Modified by jfeeney

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@obach

I sympathise, as I was pretty scathing of FF 4 - it being so bad as to be unusable, in my experience.

However, I am personally finding FF 5 (Beta) to be an improvement - I'm using it now. So it may be worth giving it a try. You can get Firefox 5 betas at http://beta.mozilla.org.

BUT - I really do share your frustration at there be no admission to what was wrong. From a diagnostic and 'learning from your mistakes' standpoint, if something has gone wrong, you need to understand exactly what did and why and then you can make sure it doesn't happen again. At the moment the 'fix', for me, is to by-pass FF 4 completely and run the beta version of FF 5. I know a lot of people might not be happy running Beta versions, so it's not a complete fix, but it's a fix. A 'hands up' statement about what was wrong with FF 4 might win back some of the friends Mozilla lost.

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myself was a FF user for last 12 yrs !! even i remember recommending ppl abt it...but FF 4 is a real PAIN IN THE APPROPRIATE PLACE....

it hogs memory...for simple functions (available by default in previous vers) ,now u have to install add-ons for them (like new tab button, FF4 either lets u have a new tab button OR the "+" button near opened tabs..but U CANT HAVE THEM BOTH SAME TIME!! WHAT THE.......

PC hangs/freezes almost everytime i ran FF 4 ..and for that i have lost valuable data..mind u, my machine config is not outdated. I have reverted back to previous vers FF 3.6...and am NOT UPDATING IT SOON....

ALL OF U FOLKS HAVIN PROBS WITH FF4 : easiest solution for all your probs -

1) get rid of FF4 and install the previous vers - http://www.mozilla.com/en-US/firefox/all-older.html after backing up - https://support.mozilla.com/en-US/kb/Backing+up+your+information

OR

2) get an alternative browser

yes folks, the above solution will at least give u peace of mind and a more peaceful good night sleep

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To john99

I installed firerfox4 on a clean install of windows o nmy test rig, the ff installation was clean on a new profile. Default options and default plugins/addons, not even adblock plus installed. I loaded up about 10 tsites in to tabs and then left it idle for 1-2 days, came back and using 3 gig of ram. ouch. Restarted the ap and it repeated the same behaviour again, this went on for a a couple of weeks,again and again. Then I left it running for an entire week idle, and the app actually crashed when I came back to pc, the crash report said it was using 7.8gig of memory at time of crash. I have since discovered if I either, load the home page on current tab, open a new tab, refresh the current tab. Memory usage goes back down to its normal level. This proves a particular website is not causing a leak, it cant be a plugin as I have none loaded, and I tried toggling hardware acceleration which has no affect. This is a very severe memory leak as in under half a day memory usage will go up from 300meg to over a gig from just 'IDLING', no pages auto refreshing. Bartab will not work round this problem either, I managed to get bartab installed on ff4 and unloading background tabs has no affect. Its a very nasty bug which is a showstopper, there is 1000s of reports on here, numerous bug reports, developers will be aware of the problem but for whatever reason are ignoring it, and continue to try and push ff4 over auto update to ff3 users.

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Thanks for that chrcoluk,

This is the sort of information the developers need to track down and fix memory problems, but remember some may have been fixed and others identified already.

Clearly what you see is not expected behavior and I doubt others have reproduced it. (You will need to compare your details and tests with the bugs reported ) You seem to have built a reproducible testcase because you can list the steps taken to reproduce and only need to specify details of the defaults you are using and the sites.

May I suggest you file a bug report about this on Bugzilla. However with one proviso, that you do the test in Firefox 5. (or better still in a nightly) The reason I suggest that is because I believe some bugs will have been fixed in firefox 5 but not in Firefox 4. As you are actually crashing due to this please also include the crash signatures. (see Troubleshoot Firefox crashes (closing or quitting unexpectedly) )

I may have mentioned upthread the tracking bugs, these have been revised slightly since then and if you are interested on what has been reported and is in progress there is an explanatory Blog and the bugs are #659855-659860 with an additional one of possibly more interest to firefox 3.6 users #660577

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For those of you who just want to get on using Firefox while developers are looking to solve the problem, I found two workarounds for Firefox 4 memory issue.

The better one is here: Firefox 4 Memory Use Workaround

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I am experiencing the same issues and have all the way back during the beta testing, I have reported my issues over and over. I open firefox, windows task manager shows that FF4 uses about 120MB of memory, after about half an hour, without opening any more tabs, without having changed the websites I was in FF4 shows that is uses about 350 to 480mb of memory. Interestingly enough it does not matter what websites I am in. The number of open tabs does have a slight issue.

What's most annoying is the CPU spikes, where firefox uses 50 to 60% of the CPU usage, thus freezing the system. This happens in the background, when I am not on FF.

I am using FF4 on 4 computers, and while 2 work ok, and I don't notice that much of an issue, I do on 2 computers to the point that it's time to uninstall FF4 and just not deal with it unless Mozilla announces a fix for this issue.

This might be something that is less visible with newer computers and more visible with older processors, ...

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I started this topic as the problem with FF 4 was so pronounced and, I felt. was not down to individual users websites or ways of working.

I was very angry about Mozilla seeming to deny there was a problem - some of the responses on here seemed to bear that out.

However.....

I have posted this earlier in this topic, but in case anyone missed it.....

I sympathise, as I was pretty scathing of FF 4 - it being so bad as to be unusable, in my experience.

However, I am personally finding FF 5 (Beta) to be an improvement - I'm using it now. So it may be worth giving it a try.

You can get Firefox 5 betas at http://beta.mozilla.org.

BUT - I really do share everyone's frustration at there be no admission to what was wrong.

From a diagnostic and 'learning from your mistakes' standpoint, if something has gone wrong, you need to understand exactly what did and why and then you can make sure it doesn't happen again.

At the moment the 'fix', for me, is to by-pass FF 4 completely and run the beta version of FF 5.

I know a lot of people might not be happy running Beta versions, so it's not a complete fix, but it's a fix.

A 'hands up' statement about what was wrong with FF 4 might win back some of the friends Mozilla lost".

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Ian Seale - "A 'hands up' statement about what was wrong with FF 4 might win back some of the friends Mozilla lost". "

Ian, I did find this statement over here: https://bugzilla.mozilla.org/show_bug.cgi?id=640923#c28

Here is an extract from one of the comments - not an 'official' acknowledgement, but it at least shows that the programmers know about the issue and are working on it; also explains the rationale about releasing version 4.

Plenty of memory work was done for FF4 (see bug 598466 and bug 615199 for some examples) but some things were missed. It wasn't helped by FF4 being almost 6 months late; at some point the decision became "is this clearly better than 3.6 for the vast majority of users, despite its flaws" and the answer was deemed to be "yes". You may disagree, but that's how it happened.

Not that this excuses the problems in FF4, but maybe it makes some things clearer. Now that we have a 6 week release cycle it should allow for more gradual improvement, and less likelihood of big regressions. And there's lots of work being done behind the scenes to improve memory usage tracking, so I'm cautiously optimistic.

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<<< If you just wish to provide feedback one of the other sites may be more appropriate eg http://input.mozilla.com/en-US/feedback >>>

John99:

You might have noted that the option to provide feedback isn't available *unless* you are using the latest Firefox version.

That seems to go together with the general Mozilla approach to invariably recommending upgrading 'across the boards' and without qualification, making no distinction as to the usefulness of new or changed features to particular types of users.

When I read (or try to read) the lists that supposedly explain what's in the upgrades, I always find myself wondering who they were written for. To me, they're useless.

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Steve Ray:

I agree there are failings with Mozilla Firefox and the information provided, something I often comment on. Regarding feedback the Hendrix site was useable until recently with the feedback results info actually being generated elsewhere. I have after reading your comment made a comment to those involved (Bug622621) with some of these changes, but I doubt anything will happen as support for Firefox 3.6 can be expected to be withdrawn shortly.

IIRC I was told recently it was mozilla marketing that I would need to petition if changes were to be made to the promotion material.

Fingers crossed !! but with smaller changes between future versions some of the failing that occurred between firefox 3.6 and Firefox 4 were because of the large number of variations & feature changes between those two version, something that should not happen in future.

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I posted earlier that bypassing FF4 and running FF 5 Beta was an improvement and a form of solution.

UNFORTUNATELY....... I have to report that FF 5 Beta was given a mandatory 'upgrade' around 1st/2nd June and has now developed problems of it's own (where previously it was fine) - even in Safe Mode' - FF 5 Beta is now slow to load Tabs, it Freezes and Fails to Respond. I have raised a bug report.

It's a shame 3.6.17 is no-longer being supported, because I was considering rolling back.

I suspect that most people posting on this forum are just simply users, with only a passing, if that, interest in the technology and detail. I'm getting a little fed-up that Mozilla seem to regard their user-base as software developers.

Anyone know a simple, basic, stable browser - you know, like Firefox used to be?

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I think it's sad that people are saying "go to FF beta!" instead of saying "we're going to fix this in our current production code". FF 4.01 is not even two months old and already people are ready to throw it away instead of fixing it.

This does not inspire confidence...

I have the exact same experience as chrcoluk in 4.01, but it appears from John99's reply that Mozilla is not interested.

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John99, you say to check for malware, update flash, etc. Done. I'm still getting hangs and crashes daily. You say to post our own thread to get support. I did so and the only reply has been to come read this and another thread or file a bug report and that seems so far over my head that I'm completely lost.

I'd really appreciate someone giving me some advice on the thread I started at https://support.mozilla.com/en-US/questions/827423

Thanks. (PS need to update it with data from the last few crashes, will do so right now.)

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