Firefox Memory Leak Two weeks ago we covered over a dozen Firefox extensions that have memory leaks, and now Mozilla’s very own Jesse Ruderman has brought up a similar issue in regards to Firefox 3’s performance. Jesse said that both Mozilla employees and volunteers have been working tirelessly to fix the memory leaks that exist in Firefox 3, and in the end he hopes that “Firefox 3 uses less memory than Firefox 2 did, especially after it has been used for several hours.

One of the more interesting things that I found in the article was a mention of an “about:memory” option possibly being added to the browser. This would be used to show a breakdown of Firefox’s memory usage, and it could be just what the doctor ordered depending on how well this is implemented. Here’s a quick description of what they would like to see “about:memory” become:

When going to the about:memory page, Firefox would scan the current memory space and see how much memory various objects are using.

At the top would be a simple list of the various areas of memory that tend to eat up RAM. The ones that I can think of right now include plugin memory usage, page cache memory usage, image cache memory usage, and memory that has been freed but is still being reported by the OS as used. Any other categories that tend to use large amounts of memory should be listed here as well. Below this, there would be a total amount of memory actually being used by Firefox.

It’s hard to tell at this point how feasible some of this will be, and what I really want to see is a memory usage layout for the extensions that I have installed. This may help me identify extensions that have memory leaks, and would give me the information needed to decide what I should keep and what I should pitch. The only problem is that extensions are heavily integrated into the browser, and aren’t really separate entities that can be tracked in this way. Hopefully the brains over at Mozilla can figure out some way to do that.