Firefox has long been a kind of memory hole, consuming more memory than a Web browser needs to, in part due to a tendency toward memory leaks. Mozilla's been tracking down and plugging leaks, but Datum's developers have taken care of the problem for them with Firemin, a free tool that plugs Firefox's memory leaks and lets you manage how the browser uses memory. It's easy to use and seems to be pretty effective, too. We tried Firemin in Firefox 14 in both 32-bit and 64-bit Windows.
Firemin runs in the background, but a system-tray icon let us open the program's options as well as launch Firefox normally and in Safe Mode. Firemin's Options dialog has a slider for configuring how it optimizes Firefox for your system. To the red-tinted left end of the slider, Firemin shows a CPU; to the right of the bar, the spectrum shifts to green and the program displays a tiny stick of RAM. The bar graphically illustrates how Firemin optimizes Firefox: The more optimization you set, the faster Firefox runs, but it required more processing power. Sliding the control to the left puts the emphasis on RAM. Firemin also displays the amount of RAM allocated to Firefox numerically, from 100 to 1,000MB. By default, Firefox doesn't launch automatically with Firemin, but we could set the option to launch the browser normally or in safe mode when Firemin starts. Finally, we could specify different Firefox installations by browsing to a different folder than the default installation.
We tried surfing with Firefox with Firemin set at either extreme. Our test system has but two Pentium 4 processor cores but 8 GB of RAM, and our favorite sites seemed to load a bit faster with Firemin's slider set all the way to the right. On systems with less memory available for Firefox, we can see how shifting the burden onto your processor makes sense. In any case, we like having the ability to customize how Firefox uses memory in our system. Add its leak-plugging potential, and this freeware will find a place next to many Firefox installations.