Rules_optimization is a project mainly written in PHP, it's free.
Optimization of rule sets of Drupal 7
$Id: README.txt,v 1.1 2010/07/10 11:37:44 saubhagya Exp $
Rules is an important module for administrator to defining condition based actions, besides this it is used by several other modules. So the performance of this module is vital. For a large rule sets current strategy is not optimized one. This project aims at to developing a module which will do optimization for condition evaluation part of Rules by employing decision tree.