想要你的网站显示得更快吗？本书阐释了14条特别规则，可以将用户连接一个页面的请求响应时间减少20～25%。作为雅虎的首席性能专家，作者Steve Souders通过优化互联网上某些访问量巨大的页面，总结出了这些最佳实践。即使是像雅虎搜索和雅虎首页这样已经被高度优化过的站点，仍然得益于这些简单得令人吃惊的性能优化规则。

《高性能网站》中的规則向你解释了可以怎样优化网站中包含的Ajax、CSS、JavaScript、Flash和图片。每个规则都可以在本书的网站上找到对应的特别例子和代码片段。这些规則包括以下内容：减少HTTP连接请求、使用内容分发网络(Content Delivery Network)、在HTTP协议头添加过期时间、把部分内容变成Gzip格式、把样式表(stylesheets)放在顶部、将脚本放在底部、避免CSS表达式、外置JavaScript和CSS、减少DNS查找、将JavaScript最小化、避免重定向连接、删除重复脚本、配置ETags、生成可缓冲Ajax、

如果你在为大流量的站点编写网页并且想要优化站点访问的用户体验，这本书不可或缺。

Foreword

Preface

 A. The Importance of Frontend Performance

Tracking Web Page Performance

Where Does the Time Go?

The Performance Golden Rule

 B. HTTP Overview

Compression

Conditional GET Requests

Expires

Keep-Alive

There's More

 1. Rule 1: Make Fewer HTTP Requests

Image Maps

CSS Sprites

Inline Images

Combined Scripts and Stylesheets

Conclusion

 2. Rule 2: Use a Content Delivery Network

Content Delivery Networks

The Savings

 3. Rule 3: Add an Expires Header

Expires Header

Max-Age and mod_expires

Empty Cache vs. Primed Cache

More Than Just Images

Revving Filenames

Examples

 4. Rule 4: Gzip Components

How Compression Works

What to Compress

The Savings

Configuration

Proxy Caching

Edge Cases

Gzip in Action

 5. Rule S: Put Stylesheets at the Top

Progressive Rendering

sleep.cgi

Blank White Screen

Flash of Unstyled Content

What's a Frontend Engineer to Do?

 6. Rule 6: Put Scripts at the Bottom

Problems with Scripts

Parallel Downloads

Scripts Block Downloads

Worst Case: Scripts at the Top

Best Case: Scripts at the Bottom

Putting It in Perspective

 7. Rule 7: Avoid CSS Expressions

Updating Expressions

Working Around the Problem

Conclusion

 8. Rule 8: Make JavaScript and CSS External

Inline vs. External

Typical Results in the Field

Home Pages

The Best of Both Worlds

 9. Rule 9: Reduce DNS tookups

DNS Caching and TTLs

The Browser's Perspective

Reducing DNS Lookups

 10. Rule10:MinifyJavaScript

Minification

Obfuscation

The Savings

Examples

Icing on the Cake

 11. Rule 11: Avoid Redirects

Types of Redirects

How Redirects Hurt Performance

Alternatives to Redirects

 12. Rule 12: Remove Duplicate Scripts

Duplicate Scripts--They Happen

Duplicate Scripts Hurt Performance

Avoiding Duplicate Scripts

 13. Rule 13:Configure Elags

What's an ETag?

The Problem with ETags

ETags: Use 'Em or Lose 'Em

ETags in the Real World

 14. Rule 14: Make Ajax Cacheable

Web 2.0, DHTML, and Ajax

Asynchronous = Instantaneous?

Optimizing Ajax Requests

Caching Ajax in the Real World

 15. Deconstructing 10 Top Sites

Page Weight, Response Time, YSlow Grade

How the Tests Were Done

Amazon

AOL

CNN

eBay

Google

MSN

MySpace

Wikipedia

Yahoo!

YouTube

Index