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firefox uses too much memory

  • 7 replies
  • 14 have this problem
  • 7 views
  • Last reply by John99

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I have MacBook Pro 3.1 with 4GB RAM and a 250GB SSD. I am running now FF Version 21.0. The problem I experience is the following and I have been experiencing it since a few versions. When I run Firefox it starts to count up Inactive Memory until the point the browser becomes really slow. The only remedy to this is to quit FF and run the 'purge' command to free up blocked memory. I have done tests with FF being the only application open, all FF extensions and plugins disabled and just my start page open (www.google.ch). The result is that even when not doing anything, FF runs up inactive memory! I have been using FF since 2007 on my Mac and very happy with it, but now it has become a pain. Is there a fix to this? Or any ideas? Thanks!

I have MacBook Pro 3.1 with 4GB RAM and a 250GB SSD. I am running now FF Version 21.0. The problem I experience is the following and I have been experiencing it since a few versions. When I run Firefox it starts to count up Inactive Memory until the point the browser becomes really slow. The only remedy to this is to quit FF and run the 'purge' command to free up blocked memory. I have done tests with FF being the only application open, all FF extensions and plugins disabled and just my start page open (www.google.ch). The result is that even when not doing anything, FF runs up inactive memory! I have been using FF since 2007 on my Mac and very happy with it, but now it has become a pain. Is there a fix to this? Or any ideas? Thanks!

All Replies (7)

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I do not use Mac s , but I do not see that an inactive Firefox could have a problem running on a system with 4GB Ram. I some times open up hundreds of tabs without Firefox starting to page its memory.

I have done tests with FF being the only application open, all FF extensions and plugins disabled and just my start page open 
  • Are you sure it is Firefox using up the memory ?
  • What are you using to check memory usage ?
  • Have you tried Firefox's about:memory as mentioned in the article linked from the last post.
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Thanks, but been already there ... did not help ... As stated in my post, FF counts up inactive memory even if I have all plug-ins and extensions disabled, running one tab on google.ch and doing nothing... HW acceleration is on too... I dont have this issue with Safari and not with Chrome (downloaded earlier to test).

Any other ideas? :-)

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Thank you for the response John :-) Funny enough I don't have the issue when I use FF (latest version) on my work laptop which runs Win7. About your questions:

Are you sure it is Firefox using up the memory ? Yes, I see this pattern happen as soon as I activate FF, it's the only app that counts inactive memory up that badly. Neither Safari nor Chrome show that behavior.

What are you using to check memory usage ? I use the Mac's 'Activity Monitor' App and 'iStat Pro' on my Mac.

Have you tried Firefox's about:memory as mentioned in the article linked from the last post. Yes I did, but to be honest I don't know how to interpret the info displayed by the command :-s

Thank you!

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I do not really understand all the mass of information about:memory generates. I do however note

  • that it is dynamic and will be able to track increasing memory use and pin down what is causing that to increase.
  • it is interactive and information appears on mouse over
  • it has buttons to reduce memory use.

If you are seeing memory usage rack up so much that it slows down Firefox it should be fairly easily noticed what is increasing. How much memory usage are you seeing attributed to Firefox ?

It will help developers if you turn on telemetry so that Firefox data is collected, that will anonymously flag slow startups and high memory usage problems for instance.

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I think the problem only happens on macs like stated above you all checked the problem on windows OS... after I update my FF I am getting the same annoying response... I think it is a bug on the update... is there a way around this problem?

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There is a possibility of a memory problem on OS X. I will try to find out more by posting a crosslink in another thread.