14.10. Summary

High-performance web-application design and performance tuning is a large and complex subject that could fill up a book on its own. This chapter focused on performance-related issues in PHP 5, taking you from the design process to profiling, benchmarking, and caching techniques.

Learning about the approaches that work and are not for big sites is time-consuming, but don't give up! The two key things to remember are to strive toward a lean, effective, and elegant design, and to relentlessly profile and benchmark your code.