RealTime IT News

Server Power Draw Overstated, But Still Considerable

Just because it's a widely-held notion doesn't make a claim true. Case in point: the "conventional wisdom" in recent years was that datacenters were consuming more than 13 percent of all power in the U.S.

Toss that notion out the window. Or better yet, recycle it.

A study sponsored by Advanced Micro Devices (AMD) and led by Jonathan Koomey, Ph.D., a staff scientist at Lawrence Berkeley National Laboratories and consulting professor at Stanford University, found that in 2005, datacenters consumed approximately 45 billion kWh, or 1.2 percent of the total 3,661 billion kWh consumed in the United States. That's about the same amount as consumed by all of the color televisions in U.S. homes.

"Though we have long known that data centers worldwide consume a significant amount of energy, AMD believes Dr. Koomey's findings are a wake-up call not just for the IT industry, but also for global business, government and policy leaders," said AMD's Randy Allen, corporate vice president, Server and Workstation Division, in a statement.

"This study demonstrates that unchecked demand for data center energy use can constrain growth and present real business challenges. New generations of energy-efficient servers are now able to help provide IT departments with a path to reduce their energy consumption while still achieving the performance they require."

The study analyzed data from IDC dating from 2000 to 2005, although Koomey wrote in the report that it was difficult to get a completely accurate picture because every system is configured for maximum use, but isn't always running at full throttle.

This doesn't let datacenters and IT growth off the hook. Overall power consumption by servers has doubled between 2000 and 2005, which represents an aggregate annual growth rate of 14 percent per year for the U.S.

Almost all of this growth is attributable to growth in the number of servers, particularly volume servers, with only a small percentage associated with increases in the power use per unit. Koomey puts this figure at around 15 percent. This puts the issue of server sprawl into perspective.

"Most servers run at around five to 10 percent load, which is driving the trend toward virtualization," Koomey told internetnews.com. "You have all these servers sitting around not doing anything. So if you can take 500 servers running at five percent capacity and consolidate to 100 servers running at 25 percent, then you can get some savings there.

Koomey said that the IDC's projections for the next four years take into account efforts like virtualization and 64-bit consolidation, but power consumption is still expected to rise by about 40 percent by 2010. If server growth were to continue in 2006 to 2010 as it did from 2000 to 2005, total electricity consumption would rise by 76 percent.

The report didn't get into specific solutions and fixes for the issue. Undoubtedly that will come from AMD's marketing department. But Koomey said there is room to do a lot of work, and the low-power race that AMD and Intel  have been in is just one part of the puzzle. HP , for example, unveiled an innovative Dynamic Smart Cooling system for datacenters last fall.

"We know there's a lot of inefficiency in the datacenter. We know there's large opportunity for virtualization, improved power supplies, AC to DC conversion, the cooling systems in data centers. So there's a whole bunch of things you can do, and it's about time," said Koomey.

While the 13 percent figure may have been debunked by the study, CIOs are still facing a power and cooling nightmare, said analyst Nathan Brookwood.

"If you're the IT manager and you have a data center on the 40th floor of the Sears Building, you don't have a lot of room to expand, don't have a lot you can do to bring more power into the building or take heat out.If you want to increase your workload, you have to do it within the existing thermal footprint. That's more important than what percent of the overall economy power consumption is," he said.

Brookwood noted that many of the giant datacenters are being built in areas with hydroelectric power. Google's  new megacenter in North Carolia is close to the Tennessee Valley Authority, while Google and Microsoft  are building server farms in Oregon and Seattle, which has lots of hydroelectric power as well.