One of the main issues that I’ve always had with Firefox is the extraordinarily large amounts of memory it eats up. If I’m running Firefox 2 it normally only takes a few hours of heavy use to see the browser sky rocket to more than 750MB of memory usage, and it begins eating up 40% to 60% of my processor. The only cure is to restart Firefox, which can be a pain when I’m in the middle of something.
Mozilla has claimed before that the Firefox memory leaks are actually a caching feature, but no browser should be eating up that much memory. Firefox caches things such as pages you’ve recently visited, images, fonts, and more. All of this so that the user sees better performance, but at the expense of your computer’s memory.
Stuart Parmenter has created an extension called RAMBack that will clear most of the major caches in Firefox, thereby freeing up some of your precious memory. The extension is only for pre-release versions of Firefox 3, but it does seem to work rather well. I’ve been able to recover upwards of 10MB of memory from Firefox 3, which isn’t all that bad considering it was using 105MB at the time. That’s almost a 10% reduction.
To use the extension you’ll find a Clear Caches option in the Tools menu, or a button is available to be added to one of the toolbars.
I’ve been trying to use the Firefox 3 nightly builds more and more to test out the memory usage, and I have to say that it is getting better. From what I’ve read Mozilla is going to be focusing heavily on the performance of Firefox 3 soon, and their hope is to have it perform better than all of the previous versions. I’m keeping my fingers crossed!