Storage power consumption has gotten short shrift compared to the server side of the data center--even from storage users themselves.
"[Power consumption's] probably two or three down the list for most customers," says Greg Nightingale, manager of enterprise storage at Sirius Computer Solutions in San Antonio. "There's always some other overriding need, such as improving backups ... or improving performance."
In fact, many users realize energy cost savings almost by accident. Seth Sladek, senior systems engineer at Cambridge Health Alliance in Cambridge, MA, deployed one 3PAR InServ S800 storage server in July 2005 and another last spring to store roughly 25TB of data. Sladek's data center was filling up fast, and he felt thin provisioning would help him conserve space. But regarding power consumption, "I'd have to say that, honestly, I wasn't thinking about that per se," he says.
Working with 3PAR, Sladek calculated he would have had to purchase, and consequently power and cool, 65 disk drives if he hadn't deployed the S800s. "Is it an overwhelming energy benefit? That I'm not sure about," says Sladek. "But, certainly, I'm looking at the numbers here and I see that ... by not having x number of drives I would actually have to have powered and cooled, I'm saving money."
Overcrowded data center spaces like Sladek's lead users to consider systems with higher drive densities--and thus higher power and cooling requirements; in addition, more users are putting requests for power metrics into their requests for proposals. So some storage vendors are rethinking drive architectures in an effort to lower power and cooling costs related to the heat dissipation of disk drives.
Companies like Copan Systems and Nexsan Technologies offer storage systems built on massive array of idle disks (MAID) architectures that spin down inactive drives. Pillar Data Systems now offers "sleepy drive" technology that slows down drives when not in use. To promote its conservation features, in April Copan became the first storage company to have its products qualified for energy efficiency rebates offered by PG&E, a West Coast utilities company.
Such developments made by array vendors represent an industry shift away from the fatalistic notion that nothing can be done to reduce storage energy costs because the disks just have to keep spinning, says Jonathan Eunice, founder and principal IT advisor at Illuminata, Nashua, NH.
This means storage users should begin putting power consumption higher on their priority lists. "If power and cooling isn't on your roadmap," says Alan Grantham, storage solutions architect at Skokie, IL-based Forsythe Solutions Group, "you're not thinking ahead."