Determine which application pool’s worker process (w3wp.exe) is hogging your CPU resources. The command below can be run in a command prompt to list IIS Application Pool PID’s. To view process ID’s in task manager navigate to View | Select Columns | PID.

I’ve needed to do this several times when a single worker process was consuming too much cpu resources and needed to be killed. Stopping the application pool did not help.

%windir%/system32/inetsrv/appcmd list wp
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