Using data deduplication to save disk space on virtual machine .vhd files

One of the features of the forthcoming Windows Server 2012 is the ability to reduce disk space consumption by using a feature called Data Deduplication or simply "dedup".

The purpose of this feature is simple: take a set of files (technically, blocks of around 64k) and check to see if there are common bits. If there are, then the redundant bits can be removed and only a single copy kept, thus potentially saving a lot of disk space.

I haven't had the try the potential cost savings myself yet, but my plan is to test this feature in the coming weeks. If it turns out fruitful, then the plan is to start using the feature on my virtualization server.

Oh, one feature that might help you get additional space for your virtual machines would be the Windows Server 2012 feature called Storage Spaces. It allows you to create hard disk space from different pieces of hardware. Combined with the new ReFS file system (R for resilent) should be a pretty fool-proof storage solution, assuming physical security (theft, fire, flooding, etc.) is in control.