ASP.NET OPTIMIZATION

1. ASP.NET OPTIMIZATION

2. Why Optimize? • $$$ Whether you build applications for customers or not, enhanced applications save money.

3. Optimize Your Web Applications • Improve your code • Research strategies, methods, techniques • Revisit old code • Monitor your app • Out-of-Box • Third party • Create your own

4. String Manipulation • Use String Builders for modifying strings • Mutable Value- can be modified • appending • removing • replacing • inserting characters • More than three changes http://www.varay.com/Optimization/StringBuilderEx.aspx

5. Server.Transfer • HttpServerUtility.Transfer • Parameters • Path –URL as string • preserveForm • True- preserves QueryString and Form collections • False(default)- clears QueryString and Form collections • Terminates execution of the current page • Begins execution of a new page • Use when redirecting to another page within same application • Avoids needless client-side redirection

6. Option Strict & Option Explicit • For Visual Basic, VBScript and JScript • Late binding • expensive performance-wise • Option Explicit • forces you to declare your variables/objects before using them • set to “On” by default •   Option Strict • requires you to explicitly declare datatype conversions by disallowing late binding

7. Option Strict & Option Explicit • Project Properties- turn them “On” • In Page or Control Directive ‘<%@ %>’ • Strict="true" • Result- faster execution http://www.varay.com/Optimization/OptionStrictEx.aspx

8. Avoid Exceptions • Exceptions cause performance to suffer • Avoid relying on exceptions in your code • Anticipate exceptions • checking for null • check for specific values before applying math operations

9. Debug Mode • Disable debug mode before you • deploy a release application or • conduct performance measurements • Web.config <compilation> • Attribute- debug • Option • true- Specifies compilation of debug binaries • false- Specifies compilation of retail binaries

10. Debug Mode • Visual Studio • When building change ddl • Debug • Release • Examples .dll size • From 380kb to 364kb • From 412kb to 392kb

11. Data Access • Open fewest possible connections (connection pooling) • Data Access Layer- between Business Services and Data Services • Make use of • automatic pooling • automatic transaction handling

12. Data Access • Data Access Method • SQL Server-based data access method provided by the .NET Framework • Recommended for high performance • Stored Procedures • Additional performance boost • Instead of ad-hoc queries

13. Data Access • Advantages to Stored Procedures • Database operations • Can be encapsulated in a single command • Are optimized for best performance • Provides additional security • ADO.NET Command object • Explicitly defines stored procedure parameters • Access output parameters and return values

14. Data Access • Execute Scalar- value of the first column of the first row of the result set • Retrieves a single value • Examples- values returned by an aggregate function • Count ( * ) • Sum ( Field ) • Avg ( Field )

15. Data Access • SqlDataReader- forward-only data stream • higher performance than the DataSet class • Tabular Data Stream ( TDS ) protocol • IEnumerable interface • Instead of While Reader.Read() • Databind()

16. ViewState • Enabled by default • To disable set MaintainState property to false • per control <asp:datagrid EnableViewState="false“ … /> • per page <%@ Page EnableViewState="false" %> • per usercontrol <%@ Control EnableViewState="false" %>

17. ViewState • Light Control Group • Label • TextBox • Button • LinkButton • ImageButton • CheckBox • RadioButton • HyperLink

18. ViewState • Datagrid • DataList • Repeater • CheckBoxList

19. Session State • Disable when not using per-user session state • Configure Session State • <%@ Page EnableSessionState="false" %> • ReadOnly • web.config file <sessionstate mode="off" />

20. Session State Provider • In-process session state • Out-of-process session state as a Windows Service • Out-of-process session state in a SQL Server database

21. Server Round Trips • Avoid unnecessary round trips to the server • retrieving data • storing data • Use HTML controls instead of ASP.NET server controls • Use appropriate postback event handling • Use client side script for data manipulation

22. Cache • Avoids overhead of retrieving information from resources outside the application. • Stores • page output or • application data • Stores data on the client or on the server

23. Cache • Output caching, which caches the dynamic response generated by a request. • Fragment caching, which caches portions of a response generated by a request. • Data caching, which allows developers to programmatically retain arbitrary data across requests

24. Cache Sub Page_Load Dim objItem As DictionaryEntry For each objItem in Cache lblContents.Text &= "<li>" & objItem.Key lblContents.Text &= "=" & objItem.Value.ToString Next End Sub http://www.superexpert.com/default.aspx?id=371

25. String Manipulation http://robz.homedns.org:8080/blog/archive/2004/10/07/173.aspx http://msdn.microsoft.com/library/default.asp?url=/library/en-us/cpref/html/frlrfsystemtextstringbuilderclasstopic.asp http://msdn.microsoft.com/library/default.asp?url=/library/en-us/cpref/html/frlrfsystemstringclasstopic.asp

26. Server.Transfer http://msdn.microsoft.com/library/default.asp?url=/library/en-us/cpref/html/frlrfsystemwebhttpserverutilityclasstransfertopic.asp http://msdn.microsoft.com/library/default.asp?url=/library/en-us/cpref/html/frlrfSystemWebHttpServerUtilityClassTransferTopic.asp

27. Option Strict & Option Explicit http://authors.aspalliance.com/aspxtreme/webapps/developinghigh-performanceaspnetapplications.aspx http://robz.homedns.org:8080/blog/archive/2004/10/07/173.aspx

28. Avoid Exceptions http://authors.aspalliance.com/aspxtreme/webapps/developinghigh-performanceaspnetapplications.aspx

29. Debug http://msdn.microsoft.com/library/default.asp?url=/library/en-us/vsdebug/html/vxtskdebugmodeinaspnetapplications.asp http://authors.aspalliance.com/aspxtreme/aspnet/syntax/compilationsection.aspx http://robz.homedns.org:8080/blog/archive/2004/10/07/173.aspx http://dotnetjunkies.com/WebLog/wayfarer/archive/2004/09/30/27318.aspx

30. Data Access http://www.aspfree.com/c/a/VB.NET/Building-a-Robust-and-Highly-Scalable-Distributed-Architecture-using-VB-NET/1

31. ViewState http://webreference.com/programming/asp/viewstate