How to determine which w3wp.exe process belongs to which web site

Assuming you are debugging on non production servers, the easiest thing to do is to set the identities of each w3wp process to different accounts. I cannot find anything in IIS admin to set the title. Even when the debugger is running I cannot set the title like I can in threads. Hope this helps.

You might want to use a tool like Performance Monitor to monitor the "Process\Working Set" for the W3WP.exe process and record it to a database. You then could could correlate it to the HTTP logs for the IIS Server.

It helps to have both the Perfmon data and HTTP logs both writing to an SQL database. Then you can use T-SQL to bring up requested pages by Date/Time around the time of the observed memory pressure. Use the DatePart function to build a Date/Time rounded to the desired accuracy of Second or Minute as needed.

Hope this helps.

Thanks, -Glenn