New Data Center Strategies Newsletter, Network World, By Andreas M. Antonopoulos, Network World, 11/07/06

Power consumption has become a big issue in the data center. But with all the focus on servers, are storage systems getting an easy pass?

After all, storage arrays have one big disadvantage: moving parts. While most of the power consumption is to keep the disks spinning at high RPM, more power is used to remove the heat produced by all that spinning. Storage vendors are likely to face increasing pressure to provide power usage measurements and then reduce power consumption and heat output as much as possible.

One promising technology for power savings: Massive Arrays of Idle Disks (MAID).

In our benchmark research “The New Data Center 2006,” we found that storage growth was one the second greatest challenge for IT executives with many experiencing growth in excess of 100% compounded yearly. A lot of that storage growth was related to compliance and document retention initiatives that have mutated into “keep everything forever.” As I mentioned previously, storage growth introduces low capex costs because of cheap disks, but very high and recurring opex costs because of maintenance, operations, compliance, recovery and so forth. Add to that the power consumption of large disk arrays, and storage easily becomes a huge challenge for the next couple of years.

MAID technology was first introduced in 2002 and has been gaining interest from many companies as a solution to rampant storage growth. MAID arrays are built on inexpensive SATA drives, which provide high storage density for low cost.

In a MAID array, only about 25% of disks are spinning at any time. Disks are spun-down when not in use and spun-up again when data residing on the disk is requested. Obviously this adds latency to the retrieval time for less frequently accessed data, but should increase the life-span of disks and drastically reduce the power consumption per terabyte. MAID arrays are used by organizations most affected by compliance and requiring large amounts of near-line (not offline, but not quite online) storage.

As with server power consumption, there is a curious disconnect in the TCO of storage - the groups responsible for storage will most likely never see an electricity bill for the data center.

So storage decisions are made independently of their impact on the cost of the facilities. Many organizations (64% of participants in our benchmark research) are now merging facilities management into IT and IT operations, in a more holistic approach to data center management.

If your organization is not looking at electricity costs you might be missing a very large component of storage TCO. If you include electricity costs then you might find MAID technology a very good fit for your storage needs and a great way to save money on power. Idle hands are the devil’s tool, but idle disks could be a blessing in disguise.