I don't where to begin researching this problem, so I thought I'd ask you guys here where I could begin finding out what gone wrong with our asp.net application.
The problem: Occasionally our application gets into a state where the asp.net worker process pegs the CPU at 100% usage and stays there until IIS is shutdown/restarted. After the CPU is pegged users start getting asp.net errors all over the place.
Our application is built on top of a fairly complication DevExpress XAF (an application framework) and is deployed as an asp.net application. We've only recently started having this problem and only recently have had a lot of people (5 or more) doing their daily work using the application. I've checked the XAF application logs and don't see anything that tells me why or what causes the application to peg the CPU.
I am asking here because XAF is a complex framework, and in the past asking DevExpress for help (under the product we have with them) almost never resolves anything. They always want you to zip up you project and send it to them (our project is rather large at this point), and they rarely are able to reproduce problems or give good advice.
Has anyone here run into situations where your asp.net application uses all the CPU resources and won't let go? How can I prevent this from happening or where should I start looking (other than google and the XAF application logs which I've already done) to decide what to investigate next?