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FF 4 uses 1.6 GB of RAM

  • 3 replies
  • 10 have this problem
  • 11 views
  • Last reply by Bethzur

Bethzur
Bethzur
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Firefox 3.x wasn't very good with RAM, but 4 is just plan absurd. I have AdBlock and FireBug installed (plus QuickTime & Flash).

After viewing a bunch of web sites over a few days, I can close all of the tabs and windows down to a single one. FF still uses 1.6 GB of RAM. Eventually it will use so much Windows XP grinds to a halt thrashing the disk until I kill FF. (It's completely frozen at this point.)

It appears to allocate memory for pages, perhaps JavaScript, and never releases it. It never decreases memory usage. Right now it's using 800 MB after just a couple of days. I have two tabs open. This one and Google Reader. Closing Google Reader doesn't help.

This is completely reproducible, every few days it gets dog slow and I have to restart it. You can sort of tell tings are getting bad when you can't watch YouTube movies smoothly. The video freezes for several seconds, although the audio keeps going. Restarting FF corrects this.

Chrome and Safari don't seem to do this on my XP box.

Firefox 3.x wasn't very good with RAM, but 4 is just plan absurd. I have AdBlock and FireBug installed (plus QuickTime & Flash). After viewing a bunch of web sites over a few days, I can close all of the tabs and windows down to a single one. FF still uses 1.6 GB of RAM. Eventually it will use so much Windows XP grinds to a halt thrashing the disk until I kill FF. (It's completely frozen at this point.) It appears to allocate memory for pages, perhaps JavaScript, and never releases it. It never decreases memory usage. Right now it's using 800 MB after just a couple of days. I have two tabs open. This one and Google Reader. Closing Google Reader doesn't help. This is completely reproducible, every few days it gets dog slow and I have to restart it. You can sort of tell tings are getting bad when you can't watch YouTube movies smoothly. The video freezes for several seconds, although the audio keeps going. Restarting FF corrects this. Chrome and Safari don't seem to do this on my XP box.

All Replies (3)

Álvaro González
Álvaro González
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I think most of the memory leaks are caused by the use of extensions. In particular, there's a bug in Firefox that prevents Firebug from releasing memory when you download large files:

http://getfirebug.com/knownissues

In any case, some versions ago I got used to restarting Firefox each two or three hours of browsing and it seems it's still necessary.

Real Lowlander
Real Lowlander
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As I long time FF user (1st 20,000 downloaders) I am so disappointed with 4.0. I find similar problem. 3.6.16 used approx. 6% of 2Gb RAM, 4 has been reported at 25%. Not caused by extensions as installed over 3.6 with no change in same few exts. Many other problems (e.g. 4 fails to remember allowed redirects & many undesired changes) so resorted to backup of 3.6. Not a definitive answer, but one sure to work is to install a totally portable version of 3.6.16 (or even 4 if you wish to play around with it), there are many portable versions available which do not mess with anything else on your machine, just Google Firefox Portable. I almost exclusively use Portable progs. for everything nowadays and if issue crops up it is as simple as deleting the folder it was installed in. Also it can be copied to a Flash Drive complete with all exts. & settings and used on any win os PC. This is a good recommendation.

Bethzur
Bethzur Question owner
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I rarely download files, so I don't that's the problem.