Optimize SQLite Databases In Firefox - gHacks Tech News

Optimize SQLite Databases In Firefox

The Mozilla Firefox development team has changed the way the web browser stores information to SQLite databases in Firefox 3.

Cookies, Bookmarks, RSS feeds and many other information are now stored in SQLite databases that are stored in the Firefox profile.

A problem that can arise is that a database can get fragmented over time which inflates its size and can have the consequence that users on the system notice performance drops because of it. This happens for instance when Firefox attempts to pull data from a database for example.

It is possible to optimize SQLite databases to defragment them so that their size decreases performance bottlenecks are dealt with.

The website Web Upd8 explains how to optimize the SQLite databases of Firefox running under Windows, Linux or Mac OS. Windows users for example need to download a batch file and place it into the Firefox profile that they want to optimize.

The batch file will run the vacuum command on all SQlite databases that are located in the profile folder.

The effect of the optimization depends largely on the fragmentation of the SQLite databases.

Optimization on a test system reduced the size of the Firefox profile folder from 64.8 Megabytes to 53.4 Megabytes. Users with many bookmarks and RSS feeds will most likely see a large size reduction of the profile folder while users who use Firefox only occasionally will see little to no improvement.

Update: Places Cleaner is a free extension for Firefox that you can use to vacuum the Places database of the browser containing history and bookmark information. Once installed, tap on the Alt key and select Tools > Places Cleaner > Clean Now from the menu that opens up.

Mozilla suggests not to vacuum the database manually on the other hand.


We need your help

Advertising revenue is falling fast across the Internet, and independently-run sites like Ghacks are hit hardest by it. The advertising model in its current form is coming to an end, and we have to find other ways to continue operating this site.

We are committed to keeping our content free and independent, which means no paywalls, no sponsored posts, no annoying ad formats or subscription fees.

If you like our content, and would like to help, please consider making a contribution:

Previous Post: «
Next Post: »


  1. xdmv said on July 11, 2009 at 1:00 pm

    Is there any way to limit the size of this databases?
    Thanks in advance!

    1. Martin said on July 11, 2009 at 1:03 pm

      There is no automatic way to limit the size. You have to do it manually.

  2. paulus said on July 11, 2009 at 2:30 pm

    Really great find Martin this works, ferry well.

  3. stream said on July 11, 2009 at 6:39 pm

    wow nice info. .thx

  4. Thufir said on October 14, 2014 at 6:00 am

    where are rss feeds stored, exactly?

Leave a Reply

Check the box to consent to your data being stored in line with the guidelines set out in our privacy policy

Please note that your comment may not appear immediately after you post it.

Be polite: we do not allow comments that threaten or harass, or are personal attacks. Please leave politics and religion out of discussions!