I'm now generating a xml in to a string from database and but for many data like 15000 data it took almost 83 minutes.

Roseanne Zhang

I guess you would never need 15000 records for XSL transform and display. Therefore, you need only to load the data needed, and show the user. Load other data on needed bases. This is the general concept of GoF proxy design pattern. There are many ways to implement it. Try to find one fit your needs.