Consolidating servers to save energy in the data center is well under way in many enterprises. Now, attention is turning toward greening up the storage array, which poses much more of a challenge.
That's because the major energy issue surrounding storage isn't one of utilization. Bumping servers from 20 percent efficiency to 80 percent is a no-brainer, but most storage systems are over-provisioned on purpose to ensure there is always enough capacity to meet operational needs. Lower that ceiling and you increase the risk to vital business operations. You can add capacity, but that means more drives drawing more energy.
So far, the storage industry has responded through techniques like deduplication and compression to cut down on data loads or drive management to cut power to idle disks. For the most part, these do help reduce power consumption, but not nearly to the level of server consolidation.
But some new approaches are showing much more promise. One of them is flash technology, which is not altogether new but is finally starting to show the kind of robustness needed for mission-critical applications. Yesterday we reported on Micron Technology's new RealSSD system, which the company says maintains an MTBF of more than 2 million hours and draws only 2.5 watts when active. That's better than hard disk drives on both counts by far.
Another innovative approach is a new appliance from a company called PowerFile. The Active Archive Appliance (A3) scales up to 280 TB (although in a whopping 42U enclosure) and provides about 700 TB per kilowatt, barely 5 percent of a traditional disk-based array. The system uses a combination of disk-based cache and Blu-ray technology, combined with virtualization software that links storage subsystems into pools that can be managed as a single volume or as multiple smaller volumes.
Still another inviting solution is "heterogeneous virtualization," described here by Sys-Con's David Hubbard. By connecting multiple heterogeneous arrays to a single storage system, you essentially create numerous virtual storage systems out of a single entity. Each system can provide differing levels of service, so you no longer have to provide numerous storage infrastructures to accommodate various types of data. Mission-critical data can share the same system as near-line or backup storage.
Continued focus on energy efficiency may benefit the data center industry, but unfortunately it may not be in the long-term interests of the storage vendors. This interesting article by storage consultant Steve Denegri on the SCSI Trade Association Web site describes the fate of numerous industries that have strived for energy efficiency only to see their revenue potentials max out, followed by weakening performance and rapid industry consolidation as too many vendors start chasing too few dollars. He recommends a renewed focus on cheaper energy, rather than more efficient systems.
For good or ill, though, it seems energy efficiency is the name of the game right now. Denegri recommends that storage firms give their customers what they need (more and better storage) rather than what they want (more efficiency) because it will be better for them (the customers) in the long run. In the short run, however, that's certain to be a losing strategy.