Smith - Professional website performance: optimizing the front-end and back-end

CONTENTS

Professional Website Performance: Optimizing the Front End and the Back End

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John Wiley & Sons, Inc.

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Copyright 2013 by John Wiley & Sons, Inc., Indianapolis, Indiana

Published simultaneously in Canada

ISBN: 978-1-118-48752-5

ISBN: 978-1-118-48751-8 (ebk)

ISBN: 978-1-118-55172-1 (ebk)

ISBN: 978-1-118-55171-4 (ebk)

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To my wife, Stef, and my parents

ABOUT THE AUTHOR

PETER G. SMITH has been a full-time Linux consultant, web developer, and system administrator, with a particular interest in performance for the past 13 years. Over the years, he has helped a wide range of clients in areas such as front-end performance, load balancing and scalability, and database optimization. Past open source projects include modules for Apache and OSCommerce, a cross-platform IRC client, and contributions to The Linux Documentation Project (TLDP).

ABOUT THE TECHNICAL EDITOR

JOHN PELOQUIN is a software engineer with back-end and front-end experience ranging across web applications of all sizes. Peloquin earned his B.A. in Mathematics from the University of California at Berkeley, and is currently a lead engineer for a healthcare technology startup, where he makes heavy use of MySQL, PHP, and JavaScript. He has edited Professional JavaScript for Web Developers, 3rd Edition by Nicholas Zakas (Indianapolis: Wiley, 2012) and JavaScript 24-Hour Trainer by Jeremy McPeak (Indianapolis: Wiley, 2010). When he is not coding or collecting errata, Peloquin is often found engaged in mathematics, philosophy, or juggling.

CREDITS

EXECUTIVE EDITOR

Carol Long

PROJECT EDITOR

Kevin Shafer

TECHNICAL EDITOR

John Peloquin

PRODUCTION EDITOR

Rosanna Volis

COPY EDITOR

San Dee Phillips

EDITORIAL MANAGER

Mary Beth Wakefield

FREELANCER EDITORIAL MANAGER

Rosemarie Graham

ASSOCIATE DIRECTOR OF MARKETING

David Mayhew

MARKETING MANAGER

Ashley Zurcher

BUSINESS MANAGER

Amy Knies

PRODUCTION MANAGER

Tim Tate

VICE PRESIDENT AND EXECUTIVE GROUP PUBLISHER

Richard Swadley

VICE PRESIDENT AND EXECUTIVE PUBLISHER

Neil Edde

ASSOCIATE PUBLISHER

Jim Minatel

PROJECT COORDINATOR, COVER

Katie Crocker

PROOFREADER

Nancy Carrasco

INDEXER

Robert Swanson

COVER DESIGNER

Ryan Sneed

COVER IMAGE

Henry Price / iStockphoto

ACKNOWLEDGMENTS

A LOT OF PEOPLE HAVE BEEN INVOLVED in making this book happen. Id like to thank everyone at Wiley for their hard work, especially Carol Long for having faith in my original idea and helping me to develop it, and Kevin Shafer, my Project Editor, who patiently helped turn my manuscript into a well-rounded book. Special thanks are also due to John Peloquin, whose technical review proved invaluable.

Id also like to take the opportunity to thank my friends and family for being so supportive over the past few months.

INTRODUCTION

THE PAST DECADE has seen an increased interest in website performance, with businesses of all sizes realizing that even modest changes in page loading times can have a significant effect on their profits. The move toward a faster web has been driven largely by Yahoo! and Google, which have both carried out extensive research on the subject of website performance, and have worked hard to make web masters aware of the benefits.

This book provides valuable information that you must know about website performance optimization from database replication and web server load balancing, to JavaScript profiling and the latest features of Cascading Style Sheets 3 (CSS3). You can discover (perhaps surprising) ways in which your website is under-performing, and learn how to scale out your system as the popularity of your site increases.

At first glance, it may seem as if website loading speeds arent terribly important. Of course, it puts off users if they must wait 30 seconds for your page to load. But if loading times are relatively low, isnt that enough? Does shaving off a couple of seconds from loading times actually make that much of a difference? Numerous pieces of research have been carried out on this subject, and the results are quite surprising.