Sukhbir Singh

Mozilla Firefox is slowly becoming the de facto web browser – making people finally realize that IE is pathetic. On a personal level, almost all of my sane friends use Firefox (thanks to me!) . This post deals with the memory leak problem in Firefox (what a memory leak is; explained further)

Programmers are familiar with the term memory leak. For others, memory leak is un-intentional memory consumption by the program wherein it fails to release memory no longer needed. Think of it like this – whenever you run a software, a specific amount of memory is allocated to it. Since we are dealing with Firefox, let us concentrate on that. When you open Firefox assuming an empty page, it takes up some amount of memory to load the interface. Next, supposing you open Gmail. The memory consumption increases (cause of Gmail). After that you sign out of Gmail and once again return to an empty page. If Firefox is still consuming the same amount of memory it was when Gmail was open – this is a memory leak. Gmail is no longer loaded but Firefox has failed to release the memory it allocated. This way the leaked-out memory keeps on increasing and hence slows down your computer if you have less RAM. (Programmers: memory leak does not mean that the memory is physically lost, it means that the program logic can’t access the memory due to faulty code)

“To check how much memory Firefox is using:”

Right click on the Taskbar and choose Task Manager. Now choose the Processes tab. Look for firefox.exe And note down the memory usage.

Typically, if you have no open windows or tabs (a blank page; which can also be brought about by typing about:blank in the address bar), Firefox should not consume more than 50 MB of memory. Anything more than this and means memory has already leaked out. (just a sentence!) Time for action.

1. The easiest solution is to restart Firefox. This will bring the memory back to a level it should actually consume.

2. Many a times, the themes and extensions cause a memory problems. The way to check this is to start Firefox in safe mode. To do this, go to Start > Run. Enter:

firefox -safe-mode

Press Enter. This starts Firefox in safe mode. Now check the memory usage after using it for sometime. If memory allocated decreases dramatically, means that the themes or the extensions are causing problems. Using the default theme or updating that extension might help.

3. Clearing the Firefox cache might help. To do this, press Ctrl + Shift + Del in succession.

4. Another method to cure the memory leak problem. Click here. (For advanced users only)

The ironical thing is that the Mozilla guys have done nothing to resolve this issue. For most people the easiest way out is method number one. Restarting Firefox.

Advanced people who know how to mess around with about:config, check the link in point 4.

Firefox rocks. Except the memory problem and loosing bookmarks!