MySQLTuner is a script written in Perl that will assist you with your MySQL configuration and make recommendations for increased performance and stability. Within seconds, it will display statistics about your MySQL installation and the areas where it can be improved.
It's key to remember that MySQLTuner is a script which can assist you with your server, but it is not the solution to a badly performing MySQL server. The best performance gains come from a thorough review of the queries sent to the server, and an evaluation of the MySQL server itself. A qualified developer in your application's programming or scripting language should be able to work with a MySQL database administrator to find improvements for your server. Once the server and application are optimized well, you may need to consider hardware upgrades to the physical server itself.