What does the symbol [/] mean in NHibernate Profiler?

Question

What does this little symbol mean in NHProf? Why is it there in Session #1 but not Session #3?

Answer 1

The [] section represents the URL that this session is bound to. [/] means the root URL of your application.

Session #3 has not been executed from the asp.net pipeline (NHibernate may be used from a background thread), and there is no URL to show.