技巧16：在任何可能時(shí)使用Server.Transfer，而不要用Response.Redirect

　　Response.Redirect告訴瀏覽器請(qǐng)求另一個(gè)不同的頁(yè)面，這常常用于引導(dǎo)用戶到登錄頁(yè)面或者出錯(cuò)處理頁(yè)面。由于重定向強(qiáng)迫了一個(gè)新頁(yè)面請(qǐng)求，結(jié)果是瀏覽器必須要與Web服務(wù)器循環(huán)2次，并且Web服務(wù)器必須處理一個(gè)額外的請(qǐng)求。IIS5.0引進(jìn)了一個(gè)新功能Server.Transfer，它執(zhí)行在同一服務(wù)器上的頁(yè)面?zhèn)鬏敚@將避免額外的瀏覽器－Web服務(wù)器的數(shù)據(jù)循環(huán)，形成良好的系統(tǒng)性能，對(duì)于用戶也有較好的響應(yīng)時(shí)間。

技巧17：避免使用服務(wù)器變量

　　存取服務(wù)器變量導(dǎo)致Web站點(diǎn)建立一個(gè)特殊的請(qǐng)求并收集所有的服務(wù)器變量，而并不是你要求的那個(gè)變量。這類(lèi)似于在文件夾中取回一個(gè)特殊的文件，要想取回一個(gè)文件，就得首先獲取所在文件夾的信息。

　　不要存取非法的Request對(duì)象（比如Request（"Data"）），對(duì)于那些不在Request.Cookies、Request.Form、Request.QueryString或者Request.ClientCertificate中的項(xiàng)目，隱含就指向了Request.ServerVariables變量，而這些變量要比其他集合對(duì)象慢得多。

技巧18：調(diào)整Web服務(wù)器

　　有幾個(gè)IIS調(diào)整參數(shù)可以提高站點(diǎn)性能。比如，對(duì)于IIS4.0，我們經(jīng)常發(fā)現(xiàn)提高ASP ProcessorThreadMax參數(shù)能夠產(chǎn)生重大的效果，特別是在那些要等待后臺(tái)資源比如數(shù)據(jù)庫(kù)或中間件產(chǎn)品的站點(diǎn)。在IIS5.0中，你可以發(fā)現(xiàn)調(diào)整ASP線程通道要比調(diào)整AspProcessorThreadMax效果更佳。

最佳的配置設(shè)定取決于應(yīng)用程序代碼、支持的硬件設(shè)備以及客戶端的工作量。發(fā)現(xiàn)最佳配置的唯一方法就是測(cè)試。

相關(guān)參考資源
Optimizing ASP scripts Developing Scalable Web Applications Got Any Cache? by Nancy Winnick Cluts Maximizing the Performance of Your Active Server Pages by Nancy Winnick Cluts 15 Seconds: Performance Section Enhancing Performance in ASP - Part I by Wayne Plourde When is Better Worse? Weighing the Technology Trade-Offs by Nancy Winnick Cluts Speed and Optimization Resources by Charles Carroll Tuning IIS The Art and Science of Web Server Tuning with Internet Information Services 5.0 Leveraging ASP in IIS 5.0 by J.D. Meier Tuning IIS 4.0 for High Volume Sites by Michael Stephenson Tuning Internet Information Server Performance by Mike Moore Navigating the Maze of Settings for Web Server Performance Optimization by Todd Wanke Managing Internet Information Server 4.0 for Performance by Hans Hugli ADO and SQL Server Top Ten Tips: Accessing SQL Through ADO and ASP by J.D. Meier Improve the Performance of your MDAC Application by Suresh Kannan Pooling in the Microsoft Data Access Components by Leland Ahlbeck and Don Willits SQL Server: Performance Benchmarks and Guides Improving the Performance of Data Access Components with IIS 4.0 by Leland Ahlbeck Microsoft Data Access Components (MDAC) and ActiveX Data Objects (ADO) Performance Tips by Leland Ahlbeck Microsoft SQL Server 7.0 Practical Performance Tuning and Optimization - The Server Perspective by Damien Lindauer Microsoft SQL Server 7.0 Practical Performance Tuning and Optimization - The Application Perspective by Damien Lindauer Accessing Recordsets over the Internet by Dino Esposito ASP components and threading models ASP Component Guidelines by J.D. Meier Q243548: INFO: Design Guidelines for VB Components under ASP Threading Models Explained by Nancy Winnick Cluts So Happy Together? Using ActiveX components with Active Server Pages by Nancy Winnick Cluts Developing Active Server Components with ATL by George Reilly Agility in Server Components by Neil Allain Building High-Performance Middle-Tier Components with C++ by Jon Flanders Active Server Pages and COM Apartments by Don Box House of COM: Active Server Pages by Don Box House of COM: Contexts by Don Box House of COM: Performance Trade-offs of the Windows 2000 Component Execution Environment by Don Box Building COM Components That Take Full Advantage of Visual Basic and Scripting by Ivo Salmre Component Design Principles for MTS Dictionary components Creating a Page Cache Object by Robert Coleridge Abridging the Dictionary Object: The ASP Team Creates a Lookup-Table Object by Robert Carter Caprock Dictionary Site Server Commerce Edition includes a dictionary component Session state Q175167: HOWTO: Persisting Values Without Sessions Q157906: HOWTO: How To Maintain State Across Pages with VBScript XML-based Persistence Behaviors Fix Web Farm Headaches by Aaron Skonnard House of COM: Stateless Programming by Don Box Performance and scalability Blueprint for Building Web Sites Using the Microsoft Windows DNA Platform Server Performance and Scalability Killers by George Reilly Microsoft Visual Studio Scalability Center Fitch & Mather Stocks 2000 Tuning the FMStocks Application High-Performance Visual Basic Apps by Ken Spencer Duwamish Books, Phase 4 Top Windows DNA Performance Mistakes and How to Prevent Them by Gary Geiger and Jon Pulsipher Building from Static HTML to High-Performance Web-Farms by Shawn Bice Tools Microsoft Web Application Stress Tool I Can？ Stress It Enough -- Load Test Your ASP Application by J.D. Meier Windows DNA Performance Kit Monitoring Events in Distributed Applications Using Visual Studio Analyzer by Mai-lan Tomsen Books Professional Active Server Pages 3.0, Wrox Press. (Especially Chapter 26: Optimizing ASP Performance, by George Reilly and Matthew Gibbs) Microsoft Internet Information Services 5.0 Resource Guide (bundled with Windows 2000 Server Resource Kit, Microsoft Press. Microsoft Internet Information Server Resource Kit (for IIS 4.0), Microsoft Press. Programming Distributed Applications with COM and Microsoft Visual Basic 6.0 by Ted Pattison, Microsoft Press. Effective COM by Don Box, Keith Brown, Tim Ewald, and Chris Sells; Addison-Wesley. Developing Web Usability: The Practice of Simplicity by Jakob Nielsen, New Riders. ASP Web sites Microsoft TechNet for IIS LearnASP.com 4GuysFromRolla.com 15Seconds.com AspToday.com Asp101.com AspLists.com. Many specialized mailing lists including: Fast Code! ASP Advanced Not Newbie State Management Scalability Visual Basic Components XML C++/ATL Component Building UseIt.com: Web Usability ASP style ASP Best Practices by George Reilly ASP Quick Lessons by Charles Carroll Planning for ASP by John Meade ASP Guidelines by J.D. Meier XML Inside XML Performance by Chris Lovett Inside MSXML3 Performance by Chris Lovet