Microsoft Storage Disk Pools and Spaces vDisk explained

This will explain Storage Pools and Spaces (vDisk) introduced in Windows Server 2012 and now better with Tiering and Cache.

This example will create a Pool with 4 HDDS and a Mirror vDisk based on these 4 disks. When the Pool is created and you start over to the vDisk the System will automatically creates two columns for the vDisk.

Each HDD will be tagged with a reserved Reservation of 256 MB. Information about the Pool and the Spaces will be placed there. The Stripe Size is 256 KB per default. The stripe width is in a two columns envrionment 2 x 256 KB = 512 KB

A Mirror is based on a minimum nuber of disks 2 and a Column to disk correlation 1 : 2 = 2 Disk per Colum = 2 Colums = 4 Disks

To check the columns settings ... please use PowerShell

Get-VirtualDisk | fl *

The expansion of a vDisk =

Add the same number of disk you started your vDisk. We started with 4 Disk that results in 2 columns means you need for every expansion 4 new disk in your pool and then you can expand the vDisk and then the LUN.

For best performance use the half the number of disks in your pool as columns size.

Do NOT use parity. It is very slow. Mirror will rock the performance tool !

Storage Pools and Spaces are built on LRC Erasure Code.