Examine VMware CPU Ready Times with Powershell

When your (VMware) consolidation ratios are becoming high, it might be smart to keep an eye on your vm’s CPU Ready Times. Unfortunately, by default, the VI Client will only show realtime ready time statistics. Plus you’d have to look at each vm individually. Thank God VMware for the PowerCLI! Read this document for more information on how to interpret the results.

# Variables
$OutFile = "D:\Scripts\ReadyTimes.csv"
$VIServer = "MyVIServer.domain.local"
 
# Connect to Virtual Center
$VI = Connect-VIServer $VIServer
 
$myCol = @()
ForEach ($VMHost in (Get-VMHost | Sort Name))
	{
	ForEach ($VM in ($VMHost | Get-VM | Sort Name))
		{
		# Gather Stats
		$Ready = $VM | Get-Stat -Stat Cpu.Ready.Summation -RealTime
		$Used = $VM | Get-Stat -Stat Cpu.Used.Summation -RealTime
		$Wait = $VM | Get-Stat -Stat Cpu.Wait.Summation -RealTime
		For ($a = 0; $a -lt $VM.NumCpu; $a++)
			{
			$myObj = "" | Select VMHost, VM, Instance, %RDY, %USED, %WAIT
			$myObj.VMHost = $VMHost.Name
			$myObj.VM = $VM.Name
			$myObj.Instance = $a
			$myObj."%RDY" = [Math]::Round((($Ready | Where {$_.Instance -eq $a} | Measure-Object -Property Value -Average).Average)/200,1)
			$myObj."%USED" = [Math]::Round((($Used | Where {$_.Instance -eq $a} | Measure-Object -Property Value -Average).Average)/200,1)
			$myObj."%WAIT" = [Math]::Round((($Wait | Where {$_.Instance -eq $a} | Measure-Object -Property Value -Average).Average)/200,1)
			$myCol += $myObj
			}
		Clear-Variable Ready -ErrorAction SilentlyContinue 
		Clear-Variable Wait -ErrorAction SilentlyContinue 
		Clear-Variable Used -ErrorAction SilentlyContinue 
		Clear-Variable myObj -ErrorAction SilentlyContinue
		}
	}
 
Disconnect-VIServer -Confirm:$false
 
# Export and launch output
$myCol | Export-Csv $OutFile
Invoke-Item $OutFile

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