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Firefox 25 still has memory leaks

  • 25 replies
  • 123 have this problem
  • Last reply by jpdemers

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It seems that Firefox still hasn't fixed it's memory leaks. I'm on Firefox 25.1 on Mountain Lion with 16 gigs RAM on a macbook pro with Retina. I've disabled all plugins and all add-ons and memory still seems to creep up as long as firefox is open. I also notice that CPU is always pretty high. In comparison to chrome and safari it's pretty ridiculous how much CPU and real and virtual memory Firefox needs. I do like the browser though.

Is anyone else having this problem still?

Please Note

For those sticking with Firefox

  • see this helpful advice post 505646 down thread by Wesley Branton
  • or for investigating a solution or needing your own fix see my post 521852 down thread

Thanks John, (A forum moderator.)

Modified by John99

All Replies (5)

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Hi Everyone,

Thanks for all your help - I appreciate it.

I've given up on trying to figure out Firefox. I'm up to v 27 but I haven't run any tests on it - it wastes too much time. My main browser now is Chrome, which seems to do a very good job and doesn't have any memory leaks. Firefox 27 still seems to have high CPU usage - anywhere between a 2% and 10% when stagnant, whereas chrome is between 0.5 and 2%. The other difference is that with a few browser windows open FF uses about 700MB real memory and 700MB virtual. Whereas Chrome uses 200 MB real and 350MB virtual.

At a glance it still seems to have a slight memory leak (or creep) although not nearly as bad as it was before. Nothing has changed on my end other than I have gone from FF 25 to 27.

Can't waste any more time on this.

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Hi lance000,
Sorry we could not help.

You no doubt have more than one browser installed. Good luck with using Chrome.

Thanks for posting back and letting us know the position.

For the benefit of other readers of this thread.

If Firefox has a memory leak in safe mode and with all plugins disabled the problem may be down to an issue with some particular website you are using; or undetetected malware. (Although malware problems are not common on Mac.s)

That is not possible to check without further information about the use when problems occur, but unfortunately in this instance it seems; quite understandably; the OP has worries about sharing that information or even stating the addons that are in use.

Exceptionally there may be ways we are able to help confidentially 

If someone does have such worries we could possibly consider sharing the information only between named persons, (Such as HelpDesk staff who I assume have signed confidentiality agreements ) and not put out any information publicly without your consent.
However we do not do one to one troubleshooting and I think you would need to first of all provide edited info. Edit actual site name to site S and addon to addon A OR at the very least be able to say you see the problem when only one single un-named addon is enabled; and when restricting all browsing to only one single un-named site.

Please see my post upthread 13th Jan if you have your own problem and need help

This thread is frequently viewed, approaching 3k views.

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Is one of your tabs Tumblr, by any chance? I've had this problem only after visting that particular site, where seemingly endless pages load image after image after image. For some reason, the gigabytes of memory this gobbles up are not released when you close the tab. There may be other sites that pull a similar stunt.

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If there is a problem with 'tumblr' and it is reproducible it may be worth you starting a new thread about that.

It is possible that in due course it would be worth filing a bug for the issue and possibly either looking for any regression in Firefox that causes that, or if there is a site issue maybe bring that to the attention of tumblr.

Please post back in this thread if you do decide to open your own thread by asking your own question.

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FF (27.0.1) under fully-updated Mavericks here; holding steady at 530-550 MB per Activity Monitor. I'll give it a day or two, and if it holds, I'll go to Tumbler and open up one of those endless pages.

(It was at 3.4 GB when I shut it down this morning!)

Modified by jpdemers

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