Mozilla Firefox browser version 3 and above stores a variety of configuration data such as bookmarks, history, RSS feeds, cookies, etc in its self managed and self contained SQLite databases. Over time, the database will get fragmented. The size of the database will get inflated with more and more junk data mixed together with real data. This will technically affect the browser’s performance, e.g. slow down the browser’s loading, delay the start up, CAUSE overall speed drops, etc. To boost and optimize the Firefox browser’s performance, users need to defragment the browser from time to time. By defragmenting the database, users will actually “vacuum” the database to get rid of old and junk data, thus optimizing its performance again.

Mozilla Firefox has disclosed a simple vacuum technique by running some codes in the Error Console command within the browser to defragment the SQLite database:

* Go to MenuTools -> Error Console
* Paste the following in the “Code:” text-box: Code: [Select]Components.classes["@mozilla.org/browser/nav-history-service;1"].getService(Components.interfaces.nsPIPlacesDatabase).DBConnection.executeSimpleSQL("VACUUM"); * Press Enter or click Evaluate. The database will thence be vacuumed immediately.

The PROCESS will speed up the browser’s performance once it is completed done. Nevertheless, if users do not want to try this measure or encounter problems while doing this, there are some Firefox add-ons which users can add to their Firefox browser to defragment and vacuum the SQLite database.

when I click "Evaluate", the cursor disappears for a few moments, so I think, it does something.