How to Calculate pCPU to vCPU and pMem to vMem Ratio Using PowerCLI – VirtuallyThatGuy

In my time working for an Online betting company, I use to do a lot of capacity planning and cluster over commit analysis for our IT director. This sphered me on to try and automate the process…Thanks to the vmware powercli you can automate the process with below. So once again welcome to VirtuallyThatGuy – this is a quick script to help you determine your cluster compute resource and utilisation using the below script. This one is for the cluster capacity planners. VMTurbo or Turbonomics is a better alternative If you love fancy graphs.

$outputFile = "C:\scripts\CPU-Memory-Ratio.csv"

$VC = "uk3p-vc01.lab.local","ntcp-vc01.lab.local" #Vcenter Details Here

##Connect to the vCenter

Connect-VIServer $VC #-User "rboadi@lab.local" -Password "xxxxxxx"

$Output =@()

Get-Cluster | %{

$hypCluster = $_

## get the GenericMeasureInfo for the desired properties for this cluster's hosts

$infoCPUMEM = Get-View -ViewType HostSystem -Property Hardware.CpuInfo,Hardware.memorysize -SearchRoot $hypCluster.Id |

Select @{n="NumCpuSockets"; e={$_.Hardware.CpuInfo.NumCpuPackages}}, @{n="NumCpuCores"; e={$_.Hardware.CpuInfo.NumCpuCores}}, @{n="NumCpuThreads"; e={$_.Hardware.CpuInfo.NumCpuThreads}},@{n="PhysicalMem"; E={""+[math]::round($_.Hardware.MemorySize / 1GB, 0)}} |

Measure-Object -Sum NumCpuSockets,NumCpuCores,NumCpuThreads,PhysicalMem

## return an object with info about VMHosts' CPU characteristics

$temp= New-Object psobject

$datacenter = Get-Datacenter -Cluster $hypCluster.Name

$NumVMHosts = if ($infoCPUMEM) {$infoCPUMEM[0].Count} else {0}

$NumCpuSockets = ($infoCPUMEM | ?{$_.Property -eq "NumCpuSockets"}).Sum

$NumCpuCores = ($infoCPUMEM | ?{$_.Property -eq "NumCpuCores"}).Sum

$vmdetails = Get-VM -Location $hypCluster

$NumvCPU = ( $vmdetails | Measure-Object NumCpu -Sum).Sum

$VirtualMem= [Math]::Round(($vmdetails | Measure-Object MemoryGB -Sum).Sum, 2)

$PhysicalMem = ($infoCPUMEM | ?{$_.Property -eq "PhysicalMem"}).Sum

##Calculating the vCPU to pCPU ratio AND vRAM to pRAM ratio.

if ($NumvCPU -ne "0") {$cpuRatio= "$("{0:N2}" -f ($NumvCPU/$NumCpuCores))" + ":1"}

if ($VirtualMem -ne "0") {$memRatio= "$("{0:N2}" -f ($VirtualMem/$PhysicalMem))" + ":1"}

$temp | Add-Member -MemberType Noteproperty "Datacenter" -Value $datacenter

$temp | Add-Member -MemberType Noteproperty "ClusterName" -Value $hypCluster.Name

$temp | Add-Member -MemberType Noteproperty "NumVMHosts" -Value $NumVMHosts

$temp | Add-Member -MemberType Noteproperty "NumPCPUSockets" -Value $NumCpuSockets

$temp | Add-Member -MemberType Noteproperty "NumPCPUCores" -Value $NumCpuCores

$temp | Add-Member -MemberType Noteproperty "NumvCPU" -Value $NumvCPU

$temp | Add-Member -MemberType Noteproperty "vCPU-pCPUCoreRatio" -Value $cpuRatio

$temp | Add-Member -MemberType Noteproperty "PhysicalMem(GB)" -Value $PhysicalMem

$temp | Add-Member -MemberType Noteproperty "VirtualMem(GB)" -Value $VirtualMem

$temp | Add-Member -MemberType Noteproperty "vRAM-pRAMRatio" -Value $memRatio

$Output+=$temp

}

$Output | Sort-Object Account | Export-Csv -NoTypeInformation $outputFile

Output like below

Datacenter	ClusterName	NumVMHosts	NumPCPUSockets	NumPCPUCores	NumvCPU	vCPU-pCPUCoreRatio	PhysicalMem(GB)	VirtualMem(GB)	vRAM-pRAMRatio
LON-Datacenter	DTCP-Cluster	3	6	12	8	0.67:1	48	15	0.31:1
LON-Datacenter	UK3P-Cluster	3	6	12	4	0.33:1	48	6	0.13:1
LON-MGMT-Datacenter	LON-MGMT-Cluster	2	4	8	14	1.75:1	46	41	0.89:1
USA-Datacenter	HDCP-Cluster	3	6	12	15	1.25:1	48	28.5	0.59:1
USA-Datacenter	NTCP-Cluster	3	6	12	20	1.67:1	48	56.7	1.18:1
USA-MGMT-Datacenter	USA-MGMT-Cluster	2	4	8	13	1.63:1	46	42	0.91:1

#&nbsp;
$outputFile = "C:\scripts\CPU-Memory-Ratio.csv"
$VC = "uk3p-vc01.lab.local","ntcp-vc01.lab.local"  #Vcenter Details Here
##Connect to the vCenter
Connect-VIServer $VC #-User "rboadi@lab.local" -Password "xxxxxxx"
$Output =@()
Get-Cluster | %{
$hypCluster = $_
## get the GenericMeasureInfo for the desired properties for this cluster's hosts
$infoCPUMEM = Get-View -ViewType HostSystem -Property Hardware.CpuInfo,Hardware.memorysize -SearchRoot $hypCluster.Id |
Select @{n="NumCpuSockets"; e={$_.Hardware.CpuInfo.NumCpuPackages}}, @{n="NumCpuCores"; e={$_.Hardware.CpuInfo.NumCpuCores}}, @{n="NumCpuThreads"; e={$_.Hardware.CpuInfo.NumCpuThreads}},@{n="PhysicalMem"; E={""+[math]::round($_.Hardware.MemorySize / 1GB, 0)}} |
Measure-Object -Sum NumCpuSockets,NumCpuCores,NumCpuThreads,PhysicalMem
## return an object with info about VMHosts' CPU characteristics
$temp= New-Object psobject
$datacenter = Get-Datacenter -Cluster $hypCluster.Name
$NumVMHosts = if ($infoCPUMEM) {$infoCPUMEM[0].Count} else {0}
$NumCpuSockets = ($infoCPUMEM | ?{$_.Property -eq "NumCpuSockets"}).Sum
$NumCpuCores = ($infoCPUMEM | ?{$_.Property -eq "NumCpuCores"}).Sum
$vmdetails = Get-VM -Location $hypCluster
$NumvCPU = ( $vmdetails | Measure-Object NumCpu -Sum).Sum
$VirtualMem= [Math]::Round(($vmdetails | Measure-Object MemoryGB -Sum).Sum, 2)
$PhysicalMem = ($infoCPUMEM | ?{$_.Property -eq "PhysicalMem"}).Sum
##Calculating the vCPU to pCPU ratio AND vRAM to pRAM ratio.
if ($NumvCPU -ne "0") {$cpuRatio= "$("{0:N2}" -f ($NumvCPU/$NumCpuCores))" + ":1"}
if ($VirtualMem -ne "0") {$memRatio= "$("{0:N2}" -f ($VirtualMem/$PhysicalMem))" + ":1"}
$temp | Add-Member -MemberType Noteproperty "Datacenter" -Value $datacenter
$temp | Add-Member -MemberType Noteproperty "ClusterName" -Value $hypCluster.Name
$temp | Add-Member -MemberType Noteproperty "NumVMHosts" -Value $NumVMHosts
$temp | Add-Member -MemberType Noteproperty "NumPCPUSockets" -Value $NumCpuSockets
$temp | Add-Member -MemberType Noteproperty "NumPCPUCores" -Value $NumCpuCores
$temp | Add-Member -MemberType Noteproperty "NumvCPU" -Value $NumvCPU
$temp | Add-Member -MemberType Noteproperty "vCPU-pCPUCoreRatio" -Value $cpuRatio
$temp | Add-Member -MemberType Noteproperty "PhysicalMem(GB)" -Value $PhysicalMem
$temp | Add-Member -MemberType Noteproperty "VirtualMem(GB)" -Value $VirtualMem
$temp | Add-Member -MemberType Noteproperty "vRAM-pRAMRatio" -Value $memRatio
$Output+=$temp
}
$Output | Sort-Object Account | Export-Csv -NoTypeInformation $outputFile

3 thoughts on “How to Calculate pCPU to vCPU and pMem to vMem Ratio Using PowerCLI – VirtuallyThatGuy”

Michael says:

25 January 2019 at 07:08

Hi may I know you’re formula for these?

1. VirtuallyThatGuy says:
  
  16 March 2019 at 23:20
  
  Hi Michael, please refer to the “##Calculating the vCPU to pCPU ratio AND vRAM to pRAM ratio.” section of the script
  
pac1085 says:

26 March 2021 at 12:16

Helpful script, thanks! I changed it a bit for our environment, including limiting it to only powered on VM’s. (We have a large number of decommissioned VM’s that are powered off but can’t be deleted for various reasons, and I didn’t want them included in capacity metrics since they won’t be used again)

I modified this line:
$vmdetails = Get-VM -Location $hypCluster
to
$vmdetails = Get-VM -Location $hypCluster | where-object “PowerState” -eq “PoweredOn”

and it worked well.

3 thoughts on “How to Calculate pCPU to vCPU and pMem to vMem Ratio Using PowerCLI – VirtuallyThatGuy”

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