performance monitor in iis 7 to monitor which website is using most resources (asp.net)

I am using Windows Server 2008 R2 and IIS 7.5, and am hosting multiple websites on the same webserver. Is it possible to use Performance Monitor to know on average which website is using the most resources?

I’ve added a user-defined Data Collector Set in Performance Monitor collecting data for 1 day. However, I could not find any details which hint which website is using the most resources. Which counters are crucial to monitor websites?

The generated report tells me that the top process is w3wp##1 – how can I know which website it corresponds to?

I’ve also tried to add counters for ASP.Net Applications for all object instances, however % Managed Processor Time (estimated) is 0 at all times.