The problem for a lot of organisations is that sorting out the process can seem a lot more difficult that implementing another technology led solution. But the best results come when processes manage growth effectively without being an impediment to the business and which are able to quickly accommodate new technologies (think thin-provisioning) without needing to be radically re-engineered.

For example, there are great products out there to take the load off high-end storage for applications generating scads of data. Outside of email, filing, ERP and other ‘well-known’ applications though, archiving (or subsetting) is still ‘hard’. The solution is to ensure that the question of data lifecycle is addressed during application development as part of the governance process for new applications.

Governance processes which ask the right questions at the right point in application development and deployment can help to make information management part of the culture of an IT organisation (not just the storage team). Do that and IT can be way more successful in preventing waste in the first place.

Ultimately though, that wasted space is out there today in most if not all organisations. For many, while a long-term strategy of sorting out process and governance can bring real benefits, there is still a great deal to be gained through implementation of short-term technology ‘fixes’. The solution in the short term is, as you say, to weigh the benefits in terms of storage reclamation against the cost of new technology and the effort required to implement. Just remember that the alternative will usually be buying yet more storage and perpetuating the problem.

So what does it take to quantify the effort and to justify the investments for reclamation. Some of the capex investments are quite straight forward. That is the cost of entry for getting into the game. However as Chris rightly points out that the effort involved needs to be better understood. Storage utilization is at an all time low. However if you are talking of only a few tens of terabytes virtualization may not be for you. You could possibly do a better job managing it.

From a thin provisioning perspective the reclamation happens when you move the data from a thick to thin volume. My understanding is this can be done non disruptively. Also the zero page reclaim is also done non disruptively.

The amount of space reclaimed depends upon the application and the file system. Please note your mileage could vary. I am studying this more now a days and hope to provide a deeper insight with times to come.

Anyways, a well written perspective by Chris Evans.

-Vijay Ramaswamy’ HDS