Tips And Tricks For Your ASP'NET Applications

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Tips And Tricks For Your ASP.NET Applications
Patrick J. Hynds CTO, CriticalSites, Boston and
New York Microsoft Regional Director for Boston
MCSEI, MCSD, MCDBA, MCT
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Patrick Hynds

• Enterprise Architect with Security and
  Performance specialties
• Regularly speak at technical conferences
• TechEd US and Hong Kong
• MDC in Cairo, Egypt
• DevTeach in Montreal
• DevDays in Boston and Hartford
• Security Summit in Boston and NYC
• Team lead for first Windows Logo Certified .Net
  application in the world
• Security Editor of .Net Developers Journal

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Agenda

• Building an intermediate page
• Set focus
• Outputcache (duration and page size)
• Reflection caching
• Returning multiple result sets
• SQL record paging
• Database cache invalidation

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Intermediate Page

• Problem
• Long running, expensive operation
• Prevent Refresh or Re-Submit
• Display temporary processing UI
• Client is still waiting for work to complete
• Server is still processing
• Perception is not reality
• Client is re-activated
• Multiple techniques, client script easiest

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Intermediate Page
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Set Focus

• Problem
• Large HTML Form
• Set initial focus of the Form, e.g. Button
• Enable dynamic control selection
• JavaScript focus() method
• Use ClientID of Server Control
• Page.RegisterStartupScript()
• Script that runs when page starts

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Set Focus
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Duration And Page Size

• Problem
• How much data to return
• How large should page be
• Page size does affect performance
• Larger pages slow down server
• Aim for 30K (Google is 2K!)
• Duration for OutputCache
• More tunable than most people think
• Even 1Sec duration makes a difference

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Page Size And Duration
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Reflection Caching

• Problem
• Reflection is powerful, but expensive
• 3-4 times cost of normal object creation
• Dynamic Class Loading
• Inspect or load classes at runtime
• Used by new Provider pattern
• Cache the constructor of the class
• 1/3 Cost of non-Cached
• Technique used in Forums Provider

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Reflection Caching
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Multiple Result Sets

• Problem
• Database operations are expensive
• Network IO is very costly
• Be as efficient as possible
• Use SPROCs or Parameterized SQL
• Batch Result Sets
• SqlDataReader.NextResult()
• Not as evident on local SQL (no network)

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Batched Result Set
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SQL Record Paging

• Problem
• DataGrid paging requests all records
• Only shows requested, discards others
• Return only the data you need
• Reduces time spent with DB
• Increases application throughput
• Stored Procedure paging
• Uses temporary table
• Requires knowledge of SQL indexes

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Paging Data In SQL Server
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DB Cache Invalidation

• Problem
• Keeping Cache and Database in sync
• Cache for period of time
• Optimally invalidate on data changes
• Built-in feature of ASP.NET 2.0
• Several bad techniques for ASP.NET 1.X
• Uses background thread
• Poll for database changes
• Similar model used in ASP.NET 2.0

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Database Cache Invalidation
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Summary

• Tips and Tricks to make your app better
• Tune and optimize your application
• Control data from the database
• Off-load work
• Cache as much as possible