Finding IIS Worker Processes

13 May 2013 13:37 powershell iis

How do we find out if there’s a worker process for an application pool? Note that there can be more than one worker process for each application pool. Note also that a worker process can host multiple web applications.

In IIS 7.x, you can use appcmd (which is in C:\Windows\System32\inetsrv), as follows:

> appcmd list wp
WP "8828" (applicationPool:DefaultAppPool)


There doesn’t seem to be a PowerShell equivalent for this, but we can do something like the following:

function Get-WebAppPoolWorker() {
	& $appcmd list wp |
		% {
			$m = [regex]::Match($_, 'WP "(\d+)" \((.*)\)')

			$o = New-Object PSObject
			$processId = [int] $m.Groups[1].Value

			$o | Add-Member -MemberType NoteProperty -Name ProcessId -Value $processId

			# The output from 'appcmd list apppool' has (prop1:val1,prop2:val2),
			# so we'll just deal with that.
			$props = $m.Groups[2].Value
			$props.Split(',') | % {
				$prop = $_.Split(':')
				$o | Add-Member -MemberType NoteProperty -Name $prop[0] -Value $prop[1]

			Write-Output $o