Firefox 14 was released yesterday – see my review of the new features and changes. One extra feature which didn’t make it into the official list of changes was the new panel-based Download Interface which I reviewed yesterday.
Another extra feature is improved memory management – in the form of what is known as the Incremental Garbage Collector (GC). Although included in Firefox 14, it is disabled and not officially supported yet – expect it to be enabled by default in a future version.
However, for those who can’t wait and want to give it a try, you can enable it right now. If you want to try it out:
- Open Firefox and type about:config in the address bar and press Enter. Click the “I’ll be careful I Promise” warning button to reveal a long list of preferences used in Firefox.
- Double click it to change the Value to ‘true’.
- Close the about:config tab – the new Incremental GC is now enabled.
If you have any problems (this is an unofficial feature so there may still be bugs) just revert back – follow the same process i.e. double click it again to turn it back to ‘false’.
What Is Incremental GC?
Garbage Collection (GC) refers to the freeing up of memory which is important for performance – most programs and web browsers do it to some extent. To put it simply, the GC tries to reclaim garbage – memory occupied by objects that are no longer in use e.g. Firefox tabs which have been closed.
Performing GC in one big go can cause a slowdown – Firefox can’t do anything whilst the process is running. The idea of doing it incrementally is to only do a little bit of GC at any one time. Overall, the same amount of time is spent doing GC, but each individual pause (whilst it is performed) is shorter.
With shorter GC pause times, games and other dynamic content on the web should have shorter pauses – hopefully so short that users can no longer notice them.
Is It Wise To Enable It?
Incremental GC was included in Firefox 13 too (where it was also disabled). In my own testing it has had no negative effects so far but I run a fairly tight and light Firefox anyway so had little to lose (or gain). Some users have reported significant reductions in memory usage and improved performance as a result.
Users who benefit most will likely be those with many (or badly written) add-ons or who play memory intensive games within Firefox or who open/close dozens of tabs per session.
If you have experienced slowdowns or high RAM (memory) usage in Firefox (especially if it runs out of control as the day progresses) it could be worth enabling this new feature.
If it causes problems on your specific system, disable it again and wait until it is officially launched in a later version.