asp.net mvc slow response every 45 seconds

Question

I have an MVC 4 app which is performing a slow request roughly every 45 seconds. It's normally 200ms and all requests will be 200ms for about 45 seconds before there is one for about 4500ms. Then back to 200ms.

I have no caching set up. I am however using a PrincipalContext to query AD.

I was wondering if anyone had any idea before I start setting up some profiling on the calls.

quick:

slow:

Answer 1

Thanks Pinch, but the problem was Active Domain and PrincipalContext. See the solution here, I turned off NetBIOS over TCP/IP and everything is running much better now.

Though I was displaying menu items based on the roles a user has, perhaps I'll cache these somewhere so I don't have to query AD every request.