I wanted to share a real world business example I did today showing the tremendous immediate ROI from using vSphere's new Thin Provisioning. First some really good news, you can start using thin provisioning right after you upgrade to vCenter, as this is a function of vCenter. I have confirmed this works with ESX 3.5 and higher Server releases.
In my case I had an urgent request for 540GB of extra disk space for a mission critical project. Now I didn't have that space available in my cluster but I did have thin provisioning. So I converted the three virtual machines needing this space to thin and then added the extra 180GB each needed. With thin provisioning these were my results:
Total storage used without thin provisioning: 762GB
Total storage used using thin provisioning: 111GB
Total immediate ROI Storage Savings: 651GB
Not only did I save storage costs, but I was able to go forward with meeting the emergency needs of the business! And now I can go back and request more storage and prepare in case they really use up that storage I provided.
In addition, vSphere is very flexible with being able to convert to thin and back to thick while the virtual machines are running!
Now you see why vSphere is such an awesome product and the best virtualization solution!