Firefox Memory Leaks Once Again Causing Frustrations


Firefox memory


Three and a half years after developers plugged “hundreds” of memory leaks in the Firefox browser that had slowed many PCs to a halt, memory leaks in Firefox 6.0.2 are apparently once again frustrating users.

In a number of issues posted on Mozilla’s support message board over the past several weeks, users report repeated instances of Firefox eating more than 1 GB of memory during basic tasks. Some memory leaks have been tied to browser plug-ins, while other users insist they are doing nothing exotic to cause such significant memory use.

For example, wrote one user: “Firefox 6.0.2 + Safe Mode on a clean Win7 64 install (Q6600 processor+6 (GB) Ram) AND IT STILL REACHES 1.5 (GB) of RAM.”

Some who posted on the Mozilla support board reported memory leaks expanding to eat more than 1 GB after a couple of hours of use, while others said it occurred very quickly after boot-up.

In all, more than 100 Mozilla users had reported having memory issues in recent weeks, including more than half that number in the last week.

Mozilla developers, responding to the reports, repeated standard statements about memory issues often being the result of specific web sites used, third-party software and browser extensions.

We wanted to get a look at some of these issues for ourselves, and it wasn’t very difficult to re-create the results. Just a few hours after opening a Firefox browser (with version 6.0.2), with seven tabs open running web sites including the self-refreshing Drudge Report, AOL.com’s main portal, Google Plus, Google Docs, Youtube, the New York Post’s web site, CRN.com and a local TV news web site, the combined memory usage by Firefox and one of its plug-ins ran in excess of 1 GB on a PC built with an Intel Quad Core Q6600 at 2.40 GHz, with 4 GB of RAM and running Windows 7 Professional 64 bit.

We tried the same thing on a MacBook Air running Mac OS X Lion 10.7.1 with a 1.4 GHz Intel Core 2 Duo and 2 GB of RAM, with better results on Firefox 6.0.2. There, memory usage registered just shy of 400 MB.

While this may not appear now to be more than an inconvenience to some, history here may provide a cause for concern. At the time of the Firefox 3 launch, memory leaks found by those running that browser often caused many desktops and notebooks to simply grind to a halt. And while developers at the time of Firefox 3 announced they had fixed hundreds of memory leaks, the corresponding jump in performance of industry-standard PC hardware may have quieted a number of concerns.

Since Firefox 3, for example, mainstream PCs have jumped from 1 GB or 2 GB of RAM on most systems to 4 GB or more (for those running 64-bit PCs.) With much of the PC market having been settled into higher RAM configurations for a good part of the last two years, it may not be surprising that memory leaks are once again emerging as a pain point.

If you run Firefox, now may be the time to start paying attention to how much memory the browser consumes while either in use or just sitting in the background. In Windows, you can check memory consumption by opening up the Task Manager. In a Mac, just click on the browser and in the location bar type this: about:memory. (Without the period, and without spaces in between.)

Unfortunately, it appears that Firefox memory issues aren’t something we can just forget.