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Memory leaks, half a decade on, will they EVER be fixed?

  • 4 replies
  • 8 have this problem
  • 10 views
  • Last reply by Zacariaz

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I love the interface, the way addons are managed, the ease of use and everything firefox is that IE isnt. However, one large problem going unfixed for so long is getting increasingly me pissed off- I'll have to move to chrome, because it makes firefox unusable.

Anyway, the problem...

Firefox has had memory leak issues for a LONG time.

As far as I can see, Mozilla are completely ignoring this as they continue to add more bells and whistles to FF... Further excelling the problem.

This has been a CORE problem for a VERY long time (pre 2006) and still goes entirely unfixed, as we can see here: http://i52.tinypic.com/k1tf1e.jpg

That's firefox 4.

Now I restarted firefox about 2 hours ago, because memory leaks were slowing my entire PC. Apon checking task manager, FF was using up a whopping 1700mb!

You said many memory leak issues would be fixed in version 3. Also in version 3.6. And then in version 4.


Well I'm running FF4, and I see zero, I repeat, zero improvement.


Actually, the memory leaks are getting progressively worse with time! FF was lucky to leak >500mb back in ff3, yet now in ff4 it'll happily consume more than a gig, and start churning one of my 4 cores to 100%, when all I'm doing is browsing a bloody plain text webpage.

I love the interface, the way addons are managed, the ease of use and everything firefox is that IE isnt. However, one large problem going unfixed for so long is getting increasingly me pissed off- I'll have to move to chrome, because it makes firefox unusable. Anyway, the problem... Firefox has had memory leak issues for a LONG time. As far as I can see, Mozilla are completely ignoring this as they continue to add more bells and whistles to FF... Further excelling the problem. This has been a CORE problem for a VERY long time (pre 2006) and still goes entirely unfixed, as we can see here: http://i52.tinypic.com/k1tf1e.jpg That's firefox 4. Now I restarted firefox about 2 hours ago, because memory leaks were slowing my entire PC. Apon checking task manager, FF was using up a whopping 1700mb! You said many memory leak issues would be fixed in version 3. Also in version 3.6. And then in version 4. Well I'm running FF4, and I see zero, I repeat, zero improvement. Actually, the memory leaks are getting progressively worse with time! FF was lucky to leak >500mb back in ff3, yet now in ff4 it'll happily consume more than a gig, and start churning one of my 4 cores to 100%, when all I'm doing is browsing a bloody plain text webpage.

All Replies (4)

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Wanna reply to this issue admins? Dont ignore me.


Bells and whistles over functionality.. Man.. Mozilla is turning into Apple.


Prove me wrong by replying.

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I took your queue and took a look for myself.

The animated GIF shows a sequence of events.

Opened FF4 to a home page set to a JPG on my C: drive [ 953 x 981 - 115.1kb ]

From 73,240 k up and down to settle at 6,536 k

I opened a folder of 13 tabs [ my daily cartoon read ] and it settles at 213,244 k.

close all of them and open the home page by clicking the Home button and it settles at 111,376 k.

Repeat the folder open again [ loads from cache this time? ] settles at 220,172 k.

Close them all and it settles at 114,808 k.

Close Firefox and reopen it and wait for it to settle down at 7,696 k.

Close the Home page tab and it goes to 36,956 k and stays there!

NOT what I would have expected to say the least!

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Stop ignoring this admins.

I am going to bump this thread periodically until SOMEONE from mozilla simply ACKNOWLEDGES the issue.


Mozilla sweeping HUGE problems like this under the rug makes them just too much like microsoft to me.

And tbh, a microsoft product would have been fixed by now (5-6 years).


Where's this Open Source "we update and progress faster than anything" pride?

Shat on imo.

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I actually created an account just to be able to post this reply. Not something I usually do.

I just did a restart of FF, monitoring the memory usage, fully expecting the well known problem to have improved. I was a bit surprised by the initial .5GB, but I usually have a billion tab open, so I thought, hey, I'll live.

After the restart it was down by ~75%. Now that's impressive.

Time to investigate further I thought.

When to Google, typed in some well chosen keyword, as to when this problem will be improved upon. I found nothing.

This is unprofessional to say the least.

But even worse, IE9 is actually a masterpiece, from a technical point of view. Sure, the supports for various features still lag, but nothing major.

In short, I dare say that IE9 is the best browser EVER!

And that is the most embarrassing part of all.

NB. I realise that there are other browsers out there that I haven't mentioned, but I honestly believe that I'm right anyway. Crome isn't done yet, Safari is... well, Safari. Opera... No comments.

That's it for now I guess, just wanted to share my disappointment.


Please do keep bumping this thread, as I'll most certainly forget to do so.