The last time I tried Firefox 3.1, or even the trusted latest, greatest Firefox 3.0.x install, I had walked away feeling very disappointed by the performance I could get from them. The main reason for wanting to use Firefox 3.1 was Tracemonkey, which is a considerably more optimized and faster version of Spidermonkey, ideally resulting in better performance with heavily AJAX-ed applications like Gmail, Google Reader and Google Docs.

That time, Firefox 3.1, with Tracemonkey enabled, was breaking Google Apps (Spreadsheets, to be more specific), which is a complete deal-breaker for me. The Firefox 3.0 installs and the Minefield nightlys that I used to run otherwise were gobbling up about half a gigabyte of RAM, with the extensions enabled and on a Macbook with just a gigabyte of RAM, which too was a deal-breaker. Thus, I wound up in bed with Camino.

With Firefox 3.1 now getting very close to the release candidate stage, I decided it was time now give it another spin. This time without any of the extensions and with a brand new profile. And I am happy to report that it has been a nice experience till now. Google Docs no longer break even when Tracemonkey is enabled and what even more heartening is that enabling it has led to a reduction in RAM usage.

I always keep Gmail, Google Reader and Google Docs open in my browser and the lowest I have ever seen on browser, in terms of RAM usage, for the same is at 110 MB. After I enabled Tracemonkey and slapped the Google Gears extension, RAM usage has dipped to around 104 MB, often dipping under 100 MB. Now, THAT is what I call a performance boost.

There is one sore spot, though. Google Gears does not seem to work at all on Google Docs with the current set up (Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.5; en-US; rv:1.9.1b2) Gecko/20081125 Firefox/3.1b2 and Gears for OS X 0.5.4.2). It works with Google Reader, but on Google Docs it just sends you to the upgrade page, saying Gears is not installed.

Now to see if this build of Firefox has the age-old issue that has plagued all the recent Firefox versions I've used: that of the browser not freeing up RAM over prolonged periods of usage. I will update this post with my findings then.

Update on the Google Gears, Firefox situation: The news is that there is not much progress there. You can read here, how even the latest SVN build won't do the trick in getting it to work. And it is not a problem that can be fixed by changing 'install.rdf' in the Gears install.