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Firefox is supposed to have efficient memory handling, especially with the release of version 3. However, that doesn’t appear to be the case out of the box, and especially not once you’ve installed a series of plugins. To resolve this you’ll need to optimize Firefox’s memory footprint.
What Is Firefox’s Footprint?
First of all, what is a footprint? The more memory and application uses the larger the footprint it leaves. Firefox’s problem isn’t so much its memory usage as it is the amount of memory it leaks. That is, as you open more tabs, visit more websites and run more plug-ins, the Firefox footprint gets larger and larger. You can release this accumulated memory by restarting Firefox. But having to do this over and over again can be a pain. One alternative is to switch browsers. We recommend Opera. The other alternative is to reduce the Firefox footprint.
How to Reduce Firefox’s Footprint?
Before you do any of this make sure you backup your Firefox profile, so you can undo changes if necessary.
How Do I Backup My Firefox Profile?
To backup your Firefox profile all you need to do is create a new one. You’ll then be able to switch between your old and new Firefox profiles. The simplest way to create a new profile is to run Firefox from a command prompt. You’ll want to enter the following (you may need to change this depending on the location of your Firefox installation):
C:\Program Files\Mozilla Firefox\firefox.exe” -P
You’ll be taken to a screen showing a list of your profiles. If you’ve never created a new profile you will only see the default profile. Click on the Create Profile button, name your new profile, and start Firefox. Now you’re ready to begin reducing Firefox’s memory usage and thereby lowering its footprint.
Steps to Lower the Firefox Footprint (Basic)
We’re going to show you a bunch of steps you can take to minimize Firefox memory usage. The first two fixes can be made within the standard Firefox navigation. The rest will involve tinkering with Firefox’s advanced settings.
Disable Firefox Add-Ons
The first, and least technical changes you can make are to disable any add-ons (preferably all of them) that you don’t need. To do so, browse to Tools -> Add-ons, select the plug-ins you wish to disable and click on the disable button. You’ll need to restart Firefox for the changes to take effect.
Clean out History
Another memory hogging feature Firefox is the accumulation of browsing and download history. To prevent Firefox from storing excess history, browse to Tools -> Options -> Privacy, and under the history section, reduce the number of days history is kept (we used 30 days, as opposed to the default 90), and uncheck “remember what I’ve downloaded”.
Lowering the Firefox Footprint (Advanced)
For the remaining footprint lowering optimizations, you’ll be using Firefox’s advanced configuration options. To begin, navigate to the Firefox address bar and type in about:config. This will open up a slew of Firefox configuration settings. We’ll begin by signing a fixed memory cache.
Assign a Fixed Memory Cache
In the about:config window enter browser.cache.memory.enable to browse to that setting. If it’s false, double-click on it to change it to true. Right-click anywhere in the window, and select new integer (this will create a new setting (termed preference), even if an existing setting is highlighted while you right-click).
Enter your preference name as browser.cache.memory.capacity. Once you’ve done that you will be prompted for an integer value. This setting should depend on the amount of memory your machine has. If you have 1 GB of RAM, you’ll enter 16384. Basically you want to use 4096 per 265MB (1GB = 1000MB).
To find out how much memory your machine has, right-click on My Computer and select Properties. After your registration data you’ll see your computer specifications, including the amount of RAM you have. Note that Windows will not always display your total amount of RAM (for example, on this particular PC, there is a 4 GB of RAM, but only 3.37 GB are displayed).
Release Memory When Firefox Window Is Minimized
Browse back to the about:config page, right-click anywhere and select New -> Boolean. Enter your Boolean value preference name as config.trim_on_minimize, and set the value to true.
Quicken the Time It Takes to Display a Page
Back on the about:config page, right-click anywhere and select New -> Integer. Name your preference nglayout.initialpaint.delay and set its value to zero. This will cause Firefox to immediately process HTML (HyperText Markup Language – the language web pages are written in) as opposed to waiting for the page to load.
Voila – the last thing is to restart (close and open) Firefox so all your settings changes can take effect. If you’ve done all these optimizations you should have successfully lowered Firefox’s memory footprint.