DISK IOPS for VM's on VMware

Hello Folks,

A Couple weeks ago, I have worked on the enhancement of the VMware environment and a task to  limit the iops for better performance.  The following PowerCLI script will collect the Microsoft Server class VM's metrics from the a datacenter and limits IO to 500.


# script by Shankar Jadapa 28/01/2015
###############################
######## LOAD PLUGINS #########
###############################


if (-not (Get-PSSnapin VMware.VimAutomation.Core -ErrorAction SilentlyContinue)) {
    Add-PSSnapin VMware.VimAutomation.Core
}

#Connecting to the desired vCenter

 Connect-viserver -server vCenter01.local -user shankar -password jadapa

 # Collecting the information of all the required Machines

 $vms = Get-Datacenter "Dynamic"  |Get-VM | Where {$_.Guest.OSFullName -match "Microsoft Windows Server*"}

 Write-Host " Gathering informaiton is completed"
 Write-Host "Going to execute the IOPs change on the machines"

  Foreach ($vm in $vms)
{

  $DiskLimitIOPerSecond = 500
  $spec = New-Object VMware.Vim.VirtualMachineConfigSpec
  $vm.ExtensionData.Config.Hardware.Device |
  where {$_ -is [VMware.Vim.VirtualDisk]} | %{
  $dev = New-Object VMware.Vim.VirtualDeviceConfigSpec
  $dev.Operation = "edit"
  $dev.Device = $_
  $dev.Device.StorageIOAllocation.Limit = $DiskLimitIOPerSecond
  $spec.DeviceChange += $dev
}

$vm.ExtensionData.ReconfigVM_Task($spec)

Write-Host "IOPS changed on $vm"
sleep -Seconds 5
}

 #Disconnecting the connected vCenters.
 Disconnect-VIServer * -Confirm:$false -Force