高性能网站

Foreword

Preface

A.TheImportanceofFrontendPerformance

TrackingWebPagePerformance

WhereDoestheTimeGo?

ThePerformanceGoldenRule

B.HTTPOverview

Compression

ConditionalGETRequests

Expires

Keep-Alive

TheresMore

1.Rule1:MakeFewerHTTPRequests

ImageMaps

CSSSprites

InlineImages

CombinedScriptsandStylesheets

Conclusion

2.Rule2:UseaContentDeliveryNetwork

ContentDeliveryNetworks

TheSavings

3.Rule3:AddanExpiresHeader

ExpiresHeader

Max-Ageandmod_expires

EmptyCachevs.PrimedCache

MoreThanJustImages

RevvingFilenames

Examples

4.Rule4:GzipComponents

HowCompressionWorks

WhattoCompress

TheSavings

Configuration

ProxyCaching

EdgeCases

GzipinAction

5.RuleS:PutStylesheetsattheTop

ProgressiveRendering

sleep.cgi

BlankWhiteScreen

FlashofUnstyledContent

WhatsaFrontendEngineertoDo?

6.Rule6:PutScriptsattheBottom

ProblemswithScripts

ParallelDownloads

ScriptsBlockDownloads

WorstCase:ScriptsattheTop

BestCase:ScriptsattheBottom

PuttingItinPerspective

7.Rule7:AvoidCSSExpressions

UpdatingExpressions

WorkingAroundtheProblem

Conclusion

8.Rule8:MakeJavaScriptandCSSExternal

Inlinevs.External

TypicalResultsintheField

HomePages

TheBestofBothWorlds

9.Rule9:ReduceDNStookups

DNSCachingandTTLs

TheBrowsersPerspective

ReducingDNSLookups

10.Rule10:MinifyJavaScript

Minification

Obfuscation

TheSavings

Examples

IcingontheCake

11.Rule11:AvoidRedirects

TypesofRedirects

HowRedirectsHurtPerformance

AlternativestoRedirects

12.Rule12:RemoveDuplicateScripts

DuplicateScripts--TheyHappen

DuplicateScriptsHurtPerformance

AvoidingDuplicateScripts

13.Rule13:ConfigureElags

WhatsanETag?

TheProblemwithETags

ETags:UseEmorLoseEm

ETagsintheRealWorld

14.Rule14:MakeAjaxCacheable

Web2.0,DHTML,andAjax

Asynchronous=Instantaneous?

OptimizingAjaxRequests

CachingAjaxintheRealWorld

15.Deconstructing10TopSites

PageWeight,ResponseTime,YSlowGrade

HowtheTestsWereDone

Amazon

AOL

CNN

eBay

Google

MSN

MySpace

Wikipedia

Yahoo!

YouTube

Index

　　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SteveSouders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(ContentDeliveryNetwork)、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。【作者简介】　　SteveSouders，雅虎的首席性能专家，编写性能分析工具并在雅虎的开发团队中推广这些工具以及最佳实践。在加入雅虎之前，steve在几个中小型的新兴公司工作过，其中包括他自己参与创办的两个公司：HelixSystems和CoolSync。他在斯坦福大学获得管理和工程的硕士学位。