i dont know why and dont know how to resolve my problem. Actually i get a web site whoe occassionnly have UrlRoutingModule take all the cpu.
Did somebody know a test or a way i could find the problem ? It's look like mvc problem but i am not sure.
Interesting. Those are mostly for static images too, so it's possibly URL Rewrite itself, and not MVC. It looks like a problem with resolving the request cache too.
How are the disk resources on your server? Is there an excessive amount of paging? I would try to temporarily turn off URL Rewrite rules and see if you can tell which one it is. Of course if you're in production and can't reproduce this in testing, that can be difficult.
This link talks about the caching in URL Rewrite. That may help in troubleshooting it too.