Which w3wp process belongs to which App Pool

UPDATE: If your App Pools use the Identity "ApplicationPoolIdentity" then the App Pool will name will show up in the process explorer - no need to do anything else.

If Windows Task manager shows excessive resource usage (CPU or memory, mostly) for an IIS 7 worker process (w3wp.exe), it’s helpful to identify which of your application pools consumes the resources.

On IIS7

Run cmd

c:

cd \windows\system32\inetsrv

appcmd list wp

On IIS6

Run cmd

c:

cd \windows\system32

iisapp.vbs 

More info references:

Identify which w3wp.exe belongs to which Application Pool in IIS7

Which w3wp.exe process belongs to which App Pool in IIS6

 iis worker process.bat

"C:\Windows\System32\inetsrv\appcmd.exe" list wp > "IIS Worker Processes.txt"

prints out this:

WP "3792" (applicationPool:......................)
WP "6428" (applicationPool:......................)
WP "240" (applicationPool:......................)
WP "3012" (applicationPool:......................)
WP "6852" (applicationPool:......................)
WP "10876" (applicationPool:......................)
WP "8424" (applicationPool:......................)
WP "9520" (applicationPool:......................)
WP "10432" (applicationPool:......................)
WP "4952" (applicationPool:......................)
WP "10932" (applicationPool:......................)
WP "10516" (applicationPool:......................)
WP "908" (applicationPool:......................)
WP "5556" (applicationPool:......................)
WP "9948" (applicationPool:......................)
WP "11096" (applicationPool:......................)
WP "4676" (applicationPool:......................)
WP "3840" (applicationPool:......................)
WP "11048" (applicationPool:......................)
WP "9532" (applicationPool:......................)
WP "1284" (applicationPool:......................)
WP "8856" (applicationPool:......................)
WP "10868" (applicationPool:......................)
WP "4872" (applicationPool:......................)
WP "3412" (applicationPool:......................)
WP "7308" (applicationPool:......................)
WP "6316" (applicationPool:......................)

where dots are the app pool names.

To get the site ids - eg for logging folder names

"C:\Windows\System32\inetsrv\appcmd.exe" list sites > "D:\webroot\backups\BackupIIS\IISLogs\IIS Site IDs.txt"