I was asked by someone for a quick overview of Thin Provisioning and when I view this as an valuable or applicable technology.
So let me start with a quick simplified visual overview of both Thin Provisioning and Traditional (aka Thick)Provisioning.
So now that you understand the concepts of Thin Provisioning and Traditional (aka Thick) Provisioning let me quick talk about the only where I see Thin Provisioning as a valuable technology.
I look at Thin Provisioning in the same way that a Disaster Recovery (DR) provider looks at taking on new customers. If storage is your business (i.e. – You are offering a shared storage model to customer co-located in your data center) then Thin Provisioning may be a key ingredient to your business model. Let me expand on this, DR providers like SunGuard oversubscribe their data centers hedging that 100% of their customer will not have a disaster at the same time (BTW this has happened and put the provider out of business). Thin Provisioning works in the same way by providing the user with the belief that they have 100% of the capacity while in fact the capacity may be over provisioned and the storage service provider (SSP) is hedging that 100% of the user co-located on the storage array will not demand 100% of the resources at the same time.
There are some very minor management benefits that I outlined in the pictorial above but IMO given some of the pitfalls associated with Thin Provisioning these do not provide a compelling reason consider Thin Provisioning. Read and interesting article here that outlines one very real issue encountered with Thin Provisioning and NTFS.
So in conclusion if you are SSP of some sort consider Thin Provisioning otherwise go thick or go home