Here are some important tips to increase the performance of asp.net project
1. Always use database stored procedure rather than sql query.
2. Minimize session variable.
3. Use datatable instead of DataSet.
4. if you bind your control on load event always call dataReader.
5. Always close/dispose or “Using” keyword to your connection/command object.
6. Make “False ” view state of your heavy control like gridveiw or other.
7. Always use caching for your master data like country ddl, state dll and other master data.
8. use HTTP compression for your full application it will increase 50% speed.
9. Use Div rather than table/td
10. Use WCF instead of WebService.
11. Make <compilation debug=”False”> in web confi file at uploading on server.
12. Disable Session State if you’re not going to use it. By default it’s on.
<%@ Page language=”c#” Codebehind=”WebForm1.aspx.cs”
13. Turn Off ViewState if you are not using
14. Avoid throwing exceptions, and handling useless exceptions.
15. Turn off Tracing at uploading on server.
16 Always check Page.IsValid when using Validator Controls
17.Repeater Control performance is Good as compare to DataList, DataGrid, and DataView
18. Use “Connection Pooling” concept,if more user are accessing the site at one time.
20. Use external Css file rather then Inline css file.
21. Code optimization: Avoid using code like x = x +1; it is always better to use x+=1.
23. Try to use Jquery instead of Ajax Control.Jquery is much more lightweight, easy to use and relatively faster than other commonly used libraries. Using jQuery, it is possible to develop concise scripts as compared to other libraries.
24.Use the custom paging in Gridview using strore procedure or LINQ to avoid the server overload.
25.Try to minimize the database hit using cache concept.