February 25, 2007

Reduce memory consumption of Firefox

You may find system slow down when surfing website for longtime or open many tabs with Firefox. This is because Firefox required more than 100 Mb memories when surf a long time or open many tabs .There is two reasons for this.

Firefox saves 50 recently visited website in the main memory of the PC in order to facilitate quick browsing. All website opened in tabs and windows occupy memory space this space remains occupy after minimizing the windows.

For reducing unnecessarily large number of saved sites follow the step below.

Enter ‘about:config’ in the address bar. Search for ‘browser.sessionhistory.max_entries’ in the ‘PreferenceName’ list and double click on it to edit it. Change the default settings ‘50’to a smaller number or even 0 and confirm with OK. When you enter ‘1’ or ‘5’ you can still access the last visited website since they are still available on RAM. Indecently saving the history is not affected by the setting. Thus you can browse through as many sites as you want; you only need to wait for the renewed loading of these websites.

You can also instruct Firefox to release the memory space that is no longer in use. Simply right click on any space in the list of configuration settings and select the context command ‘New| Boolean’. Enter ‘config.trim_on_minimise’ and ok. Click on ‘true’ in the following dialogue and again confirm with OK. Now restart Firefox.


  1. Very helpful, thanks.

  2. it seems like the first tweak works!I have the 2nd setup along with other tweaks but no obvious improvement.

  3. forgot to mention...firefox on macosx 10.4.8

  4. because it is minimize and not minimise.

  5. Thnxs for the tip, worked really well.

  6. Thanks. I've been in this trouble for a while.