ASP.NET 2.0 Performance Guidelines

- J.D. Meier, Srinath Vasireddy, Ashish Babbar, John Allen, and Alex Mackman

Design Considerations

• Consider security and performance
• Partition your application logically
• Evaluate affinity
• Reduce round trips
• Avoid blocking on long-running tasks
• Use caching
• Avoid unnecessary exceptions

Application State

• Use static properties instead of the Application object to store application state
• Use application state to share static, read-only data
• Do not store STA COM objects in application state

Caching

• Separate dynamic data from static data in your pages
• Configure the Memory Limit
• Determine the Data to Be Cached
• Refresh your cache appropriately
• Cache the appropriate form of data
• Use output caching to cache relatively static pages
• Choose the right cache location
• Use VaryBy attributes for selective caching
• Use kernel caching on Windows Server 2003

COM Interop

• Use ASPCOMPAT to call STA COM objects
• Avoid Storing COM Objects in Session State or Application State
• Avoid storing STA objects in session state
• Do not create STA objects in a page constructor
• Supplement classic ASP Server.CreateObject with early binding

Data Access

• Use paging for large result sets
• Use a DataReader for fast and efficient data binding
• Prevent users from requesting too much data
• Consider caching data

Data Binding

• Avoid using Page.DataBind
• Minimize calls to DataBinder.Eval

Exception Management

• Implement a Global.asax error handler
• Monitor application exceptions
• Use try/finally on disposable resources
• Write code that avoids exceptions
• Set timeouts aggressively

HTTP Modules

• Avoid long-running and blocking calls in pipeline code
• onsider asynchronous events

Pages

• Trim your page size
• Enable buffering
• Use Page.IsPostBack to minimize redundant processing
• Partition page content to improve caching efficiency and reduce rendering
• Ensure pages are batch compiled
• Ensure debug is set to false
• Optimize expensive loops
• Consider using Server.Transfer instead of Response.Redirect
• Use client-side validation

Resource Management

• Pool resources
• Explicitly call Dispose or Close on resources you open
• Do not cache or block on pooled resources
• Know your application allocation pattern
• Obtain resources late and release them early
• Avoid per-request impersonation

Security Considerations

• Constrain unwanted Web server traffic
• Turn off authentication for anonymous access
• Validate user input on the client
• Avoid per-request impersonation
• Avoid caching sensitive data
• Segregate Secure and Non-Secure Content
• Only use SSL for pages that require it
• Use Absolute URLs for Navigation
• Consider using SSL hardware to offload SSL processing
• Tune SSL timeout to avoid SSL session expiration

Server Controls

• Identify the use of view state in your server controls
• Use server controls where appropriate
• Avoid creating deep hierarchies of controls

Session State

• Choose Basic Types to Reduce Serialization Costs
• If You Do Not Need Session State, Disable It
• Avoid storing STA COM objects in session state
• Use the ReadOnly Attribute When You Can

State Management

• Store simple state on the client where possible
• Consider serialization costs

String Management

• Use Response.Write for formatting output
• Use StringBuilder for temporary buffers
• Use HtmlTextWriter when building custom controls

Threading

• Tune the thread pool by using the formula to reduce contention
• Configure minIoThreads and minWorkerThreads for Burst Load
• Do Not Create Threads on a Per Request Basis
• Avoid Blocking Threads
• Avoid Asynchronous Calls Unless You Have Additional Parallel Work

View State

• If You Do Not Need View State, Disable It
• Minimize the Number of Objects You Store In View State
• Use Tracing to Analyze and Reduce the Size of Your View State

Deployment Considerations

• Avoid unnecessary process hops
• Understand the performance implications of a remote middle tier
• ASP.NET 2.0 Performance Guidelines - Deployment Considerations | Short circuit the HTTP pipeline
• ASP.NET 2.0 Performance Guidelines - Deployment Considerations | Configure the memory limit
• Disable tracing and debugging
• Ensure content updates do not cause additional assemblies to be loaded
• Avoid XCOPY under heavy load
• Consider precompiling pages
• Consider Web garden configuration
• Consider using HTTP compression
• Consider using perimeter caching

References

• See Improving ASP.NET Performance at http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dnpag/html/scalenetchapt06.asp