Hello Praveena,

In order to avoid issues with performance in WebDataGrid when loading large numbers of records, I would suggest enabling either the Virtual Scrolling or Paging behaviors in order to limit the number of records being shown in the grid at a time:

http://help.infragistics.com/Help/NetAdvantage/ASPNET/2013.1/CLR4.0/html/WebDataGrid_Sorting.html

http://help.infragistics.com/Help/NetAdvantage/ASPNET/2013.1/CLR4.0/html/WebDataGrid_Virtual_Scrolling.html

Note that custom client scripts (for instance for event handlers) which iterate through the row elements on the client can also additionally degrade performance.

Feel free to contact me if you have any questions.