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Windows 7: Firefox - Reducing Memory Usage

Firefox - Reducing Memory Usage

How to Reduce Firefox Memory Usage in Windows 7
Published by Mercurial
28 May 2009
Published by

How to Reduce Firefox Memory Usage in Windows 7
information   Information
When you use the computer, probably running many software, each of them needs ram memory. RAM is very important , because the faster the frequency of the RAM the faster the software runs. In this tutorial we will move Firefox to your hard drive instead of memory when you minimize it. When we do that, firefox will take up much less ram memory.

Here's How:
1. Open a new tab in Firefox, then type in about:config in the address bar and press enter.

2. After this, a warning message will appear. Click on IŽll be careful, I promise !.

3. In about:config settings, right click anywhere and select New and Boolean as shown below.

4. In New boolean value, type config.trim_on_minimize and click on OK.

5. Select true and click on OK.

6. Close and restart Firefox for these settings to take effect.
28 May 2009   #1

Clients: XP/Win7/ubuntu

Thanks for the tutorial. There are a few things that may be worth pointing out about using this setting.

First. if you don't wish to edit about.config you can create a file called user.js and place it in your firefox profiles directory. edit the file an enter the following line:

user_pref("config.trim_on_minimize", true);

Save the file and restart firefox. Essentially any configuration changes you want to make to aboout.config can be made by entering the appropriate setting in user.js.

Second. making this change does not actually reduce the amount of memory fx uses, it just swaps memory from RAM to disk. From the Mozillazine KB:

The config.trim_on_minimize setting (Windows only) does not reduce the amount of memory used, it just swaps memory from RAM to disk. This may make Firefox slow to "wake up". If config.trim_on_minimize is left set at the default value (false), the memory will be swapped to disk only if it is needed by another application. Therefore, for most purposes the default value is recommended.
There are also other settings which also play an important part in controlling fx memory, please look at:

Finally you may also want to look at the Ramback utility:

Hope this helps.

My System SpecsSystem Spec
28 May 2009   #2

Windows 7 Professional 64-bit

Since version 3 of firefox, it has had similar technology to free up memory used by the program so Ramback isnt necessary. Note also that that addon is 3 years old.
My System SpecsSystem Spec
28 May 2009   #3

Clients: XP/Win7/ubuntu

Quote   Quote: Originally Posted by swarfega View Post
Since version 3 of firefox, it has had similar technology to free up memory used by the program so Ramback isnt necessary. Note also that that addon is 3 years old.
Agreed, I only made reference to Ramback for completeness. The Add-0n is still compatible:

Works with:

  • Firefox: 3.0a8pre – 3.6a1pre
One other thing that I should have mentioned in my previous post is that the config.trim 'hack' actually hasn't worked since firefox 3 was released. There are numerous posts regarding this on the Mozilla forums, here's an example:

How do I (Firefox 2 behavior in Firefox 3) • mozillaZine Forums
My System SpecsSystem Spec

30 Sep 2009   #4

Windows Seven Professional

4-5 mb? realy need?
whithoyt this - 12mb! del this script
My System SpecsSystem Spec
10 Oct 2009   #5

Windows 7 Ultimate x64

Are there any other about:config tweaks anybody would recommend to speed firefox up?
My System SpecsSystem Spec
05 Jan 2010   #6

windows 7

i have a similar prob...i remeber using some feature in my windows 7 which had the option like
i paid for my RAM, make full use
conserve ram or use less ram(something like that)
The first option was default selected i applied the second one.......ever since my desktop gadgets and object dock have started to lag and when i use firefox(esp when i start FB games)... the screen flashes and aero dissappears comes back as soon as firefox is shut
My System SpecsSystem Spec

 Firefox - Reducing Memory Usage

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