Uses vSphere PowerCLI to display disk information. Most importantly, whether or not the disk is ThinProvisioned.

DisplayVMDiskInformation.ps1

# Create an empty array for results
$arrResults = @()

# Get the .net view of the virtual machines
$objVMViews = Get-View -ViewType "VirtualMachine" | Where-Object {!$_.Config.Template}

# Loop through the .net view objects representing the machines
ForEach ($objVMView in $objVMViews){
  # Loop through the .net view's devices
  ForEach ($objDevice in $objVMView.Config.Hardware.Device) {
    # Where the device is a virtual disk
    If ($objDevice.GetType().Name -eq "VirtualDisk"){
      # Create a new object to represent the virtual disk
      $objVirtualDisk = New-Object PSObject
      # Append properties to the disk object based on the view object
      $objVirtualDisk | Add-Member -Name "Name" -MemberType NoteProperty -Value $objVMView.Name
      $objVirtualDisk | Add-Member -Name "DeviceLabel" -MemberType NoteProperty -Value $objDevice.DeviceInfo.Label
      $objVirtualDisk | Add-Member -Name "FileName" -MemberType NoteProperty -Value $objDevice.Backing.FileName
      $objVirtualDisk | Add-Member -Name "DiskMode" -MemberType NoteProperty -Value $objDevice.Backing.DiskMode
      $objVirtualDisk | Add-Member -Name "SizeGB" -MemberType NoteProperty -Value ($objDevice.CapacityInKB / 1024 / 1024)
      # If there is a ThinProvisioned property, then the disk is sparse
      If ($objDevice.Backing.ThinProvisioned){
        $objVirtualDisk | Add-Member -Name "ThinProvisioned" -MemberType NoteProperty -Value $True}
      Else {
        $objVirtualDisk | Add-Member -Name "ThinProvisioned" -MemberType NoteProperty -Value $False
      }
      # Append the virtual disk object to the array of results
      $arrResults += $objVirtualDisk
    }
  }
}
# Display the results on screen
$arrResults | Format-Table