ASP.NET OPTIMIZATION

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ASP.NET OPTIMIZATION
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Why Optimize?

• Whether you build applications for customers
  or not, enhanced applications save money.

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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

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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

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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

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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

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Option Strict Option Explicit

• Project Properties- turn them On
• In Page or Control Directive lt_at_ gt
• Strict"true"
• Result- faster execution
• http//www.varay.com/Optimization/OptionStrictEx.a
  spx

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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

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Debug Mode

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

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Debug Mode

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

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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

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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

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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

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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 )

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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()

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ViewState

• Enabled by default
• To disable set MaintainState property to false
• per control
• ltaspdatagrid EnableViewState"false /gt
• per page
• lt_at_ Page EnableViewState"false" gt
• per usercontrol
• lt_at_ Control EnableViewState"false" gt

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ViewState

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

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ViewState

• Datagrid
• DataList
• Repeater
• CheckBoxList

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Session State

• Disable when not using per-user session state
• Configure Session State
• lt_at_ Page EnableSessionState"false" gt
• ReadOnly
• web.config file ltsessionstate mode"off" /gt

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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

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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

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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

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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

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Cache

• Sub Page_Load
• Dim objItem As DictionaryEntry
• For each objItem in Cache
• lblContents.Text "ltligt" objItem.Key
• lblContents.Text "" objItem.Value.ToStri
  ng
• Next
• End Sub
• http//www.superexpert.com/default.aspx?id371

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String Manipulation

• http//robz.homedns.org8080/blog/archive/2004/10/
  07/173.aspx
• http//msdn.microsoft.com/library/default.asp?url
  /library/en-us/cpref/html/frlrfsystemtextstringbui
  lderclasstopic.asp
• http//msdn.microsoft.com/library/default.asp?url
  /library/en-us/cpref/html/frlrfsystemstringclassto
  pic.asp

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Server.Transfer

• http//msdn.microsoft.com/library/default.asp?url
  /library/en-us/cpref/html/frlrfsystemwebhttpserver
  utilityclasstransfertopic.asp
• http//msdn.microsoft.com/library/default.asp?url
  /library/en-us/cpref/html/frlrfSystemWebHttpServer
  UtilityClassTransferTopic.asp

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Option Strict Option Explicit

• http//authors.aspalliance.com/aspxtreme/webapps/d
  evelopinghigh-performanceaspnetapplications.aspx
• http//robz.homedns.org8080/blog/archive/2004/10/
  07/173.aspx

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Avoid Exceptions

• http//authors.aspalliance.com/aspxtreme/webapps/d
  evelopinghigh-performanceaspnetapplications.aspx

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Debug

• http//msdn.microsoft.com/library/default.asp?url
  /library/en-us/vsdebug/html/vxtskdebugmodeinaspnet
  applications.asp
• http//authors.aspalliance.com/aspxtreme/aspnet/sy
  ntax/compilationsection.aspx
• http//robz.homedns.org8080/blog/archive/2004/10/
  07/173.aspx
• http//dotnetjunkies.com/WebLog/wayfarer/archive/2
  004/09/30/27318.aspx

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Data Access

• http//www.aspfree.com/c/a/VB.NET/Building-a-Robus
  t-and-Highly-Scalable-Distributed-Architecture-usi
  ng-VB-NET/1

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ViewState

• http//webreference.com/programming/asp/viewstate