W3WP.EXE using 100% CPU - where to start?

Question

An ASP.NET web app running on IIS6 periodically shoots the CPU up to 100%. It\'s the W3WP that\'s responsible for nearly all CPU usage during these episodes. The CPU stays pinne

Answer 1

This is a very old post, I know, but this is also a common problem. All of the suggested methods are very nice but they will always point to a process, and there are many chances that we already know that our site is making problems, but we just want to know what specific page is spending too much time in processing. The most precise and simple tool in my opinion is IIS itself.

1. Just click on your server in the left pane of IIS.
2. Click on 'Worker Processes' in the main pane. you already see what application pool is taking too much CPU.
3. Double click on this line (eventually refresh by clicking 'Show All') to see what pages consume too much CPU time ('Time elapsed' column) in this pool