Slow ASP.NET site when not providing a page name

Question

On my ASP.NET Site (.Net Framework 4.5) if a user provides a pagename such as http://staging.site.com/index.aspx the site loads as expected and the user can navigate around the entire site without issue.

If the user loads the site and than changes/visits a URL that redirects to the root http://staging.site.com/ with no page name, the first load hangs up for over a minute and than all requests thereafter are also slow.

The issue is only isolated to the users session. It does not affect other users.

Answer 1

Turns out we had enabled session variables to be used in our webapi classes. And the overhead of doing this was causing the server performance to decline significantly