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Firefox 4 on OS X may have a memory leak?

  • 8 replies
  • 547 have this problem
  • 22 views
  • Last reply by vscarafi

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Currently with only Gmail open, Firefox 4 consumes 700 MB of memory.

Occasionally, I see it consuming up to 2 GB of memory and must restart it.

Currently with only Gmail open, Firefox 4 consumes 700 MB of memory. Occasionally, I see it consuming up to 2 GB of memory and must restart it.

All Replies (8)

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I launched Firefox 4 on Friday with 4 tabs. Left work for the weekend, and came back Monday morning to Firefox using 70% of my 4.5 gigs of ram.

I'm running Ubuntu 10.10, with apt-get update; apt-get upgrade run on Friday, so it's pretty up to date.

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The same for me here. I had to stop using F4 on my Mac OS Leopard. ;( To much memory used after only a few clicks.

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I have the same problem and it's really frustrating ... i love Firefox, been a loyal user since day one, and it pains me to have to switch to Chrome ...

PLEASE fix this as soon as possible

OS: Snow Leopard 10.6.7 Firefox 4 only add on: Firebug but always disabled, all plugins updated and most disabled

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Same problem. Even in static state, memory usage keeps slowly creeping up eventually consuming 1GB.

Mac OSX 10.6.7 with only ad-block plus add-on, updated to v 1.3.6. I too have been using Firefox for ages, but have switched to chrome until this issue is solved. I want to come back to Firefox as soon as possible!

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Started Firefox in safe mode with all extensions and add-ons disabled on OS X 10.6.7 . Memory usage started at 115mb. Was up over 700mb in a short amount of time with 3 tabs running. Stayed at that level after 2 of 3 tabs closed... definite memory leak, please fix!

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I currently have 8 tabs open - 4 of which are articles on Symfony, one is the Google Maps API documentation (manual page only, not an example page with a map on it), the PHP manual and two support.mozilla.com articles (including this one) - so nothing that should be resource hungry.

FF is currently using 2.81GB of memory (and it did shoot to over 3GB a moment ago when closing a tab). I've been working with a lot of JS but have now closed that tab. Firebug is very slow, as are page refreshes. The text lags as I type.

Modified by nealio82

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We're actively working on reducing memory leaks and memory use in Firefox. This article links to some of the technical details:

http://blog.mozilla.com/nnethercote/2011/03/10/memshrink/

Firefox 5 will be released in just a few days, and already has some improvement over Firefox 4:

http://blog.mozilla.com/nnethercote/2011/05/25/firefox-5-has-fewer-leaks-than-firefox-4/

This also depends on which add-ons and web sites you use. For example, Gmail is known to leak memory (and not just in Firefox):

http://code.google.com/p/chromium/issues/detail?id=5820

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I am running on OS X 10.6.8 and get the following console message when I start up Seamonkey or Firefox:

9/13/11 12:42:01 PM seamonkey-bin[265] *** __NSAutoreleaseNoPool(): Object 0x102405c20 of class NSCFString autoreleased with no pool in place - just leaking