This blog post will show the different methods to identify the process ID (PID) for an active worker process (w3wp.exe) for an application pool
Method 1: - Internet Manager UI
Method 2: - Appcmd
Appcmd is used to list out the running worker processes. The path to the utility is not set and running directly from the command prompt will fail. Use the following instructions to set the path for the utility.
Location of appcmd.exe %systemroot%\system32\inetsrv
64-bit Windows, use Appcmd.exe from the %windir%\system32\inetsrv directory, not the %windir%\syswow64\inetsrv directory.
Set the path to the location
To start Appcmd.exe
To List the started worker processes
>appcmd list wps
For complete listing of appcmds Listing of IIS 7+ Appcmd
Method 3: - Task Manager
Method 4: - Process Explorer