The Natmaster - Natmaster.com

If you're having memory issues with Firefox, try enabling the config.trim_on_minimize option in about:config. (By default this variable does not exist yet, so you must create a new Boolean.)

The Discovery

I was experimenting with the next generation of quality browsers, and came across a surprising find.

I downloaded the latest experimental nightlie firefox trunk build (named "minefield" for it's extremely experimental nature), and was playing around with it's cool new features when I decided to check out it's memory usage. It was surprisingly low - so much so, that I decided to compare it to the recently released Opera 9 beta. (Although comparing this highly experimental build to a full-fledged beta seems like apples-to-oranges.)

The Experiment

Here I opened a few pages in tabs to get a good comparison. So it wasn't unfair, I made sure to start each browser fresh and open the pages. (Both browsers have a fast-back history mechanism that keeps some information of recently visited pages in memory - making it necessary to match up session histories also.) Amazingly Firefox was eating approximately 5mb less than Opera.

The Comparison

Five megabytes is not very much, and obviously this should vary with different pages and settings. But the real miracle here is that Moizlla managed to make firefox as small-footed (with relation to memory) as Opera - while still running in the extensible XUL-driven interface.

The great part is, that I was using the default settings - no firefox memory optimizations were in place. This means that there is still room to improve memory use if the user wishes to do so.

The Conclusion

I hear people complain about firefox's memory usage all the time. Usually, they're just being critical because they heard someone else complain. Sometimes though, they really do have memory restrictions - which is why there are so many configurable features in the browser. However, I do agree that firefox could be a little better with it's memory. Apparently, I was right. The trunk builds (which will lead to Firefox 3) have shown significant improvements in the memory foot-print area. I cannot wait to see what other improvements Mozilla has in store for the future.