High Performance Web Sites

Preface

In eighth grade, my history class studied the efficiency experts of the Industrial Revolution. I was enthralled by the techniques they used to identify and overcome bottlenecks in manufacturing. The most elegant improvement, in my mind, was the adjustable stepstool that afforded workers of different heights the ability to more easily reach the conveyor belt—a simple investment that resulted in improved performance for the life of the process.

Three decades later, I enjoy comparing the best practices in this book to that 19th-century stepstool. These best practices enhance an existing process. They require some upfront investment, but the cost is small—especially in comparison to the gains. And once these improvements are put in place, they continue to boost performance over the life of the development process. I hope you'll find these rules for building high performance web sites to be elegant improvements that benefit you and your users.

How This Book Is Organized

After two quick introductory chapters, I jump into the main part of this book: the 14 performance rules. Each rule is described, one per chapter, in priority order. Not every rule applies to every site, and not every site should apply a rule the same way, but each is worth considering. The final chapter of this book shows how to analyze web pages from a performance perspective, including some case studies.

Chapter 1, explains that at least 80 percent of the time it takes to display a web page happens after the HTML ...