Blades + virtualization + multicore = power savings
There’s likely no topic hotter in IT right now than virtualization, the practice of running several virtual servers on a single physical host. About a year ago, you might have said the same thing about blade servers, a computer on a card that relies on its enclosure for power and connectivity. Multicore processors were a high-profile innovation before that. All of them boast power savings advantages, but, says Jonathan Eunice, founder and principal IT advisor of research firm Illuminati, “Any one of them on its own is kind of a ‘yeah, yeah’ proposition.”
Together, though, they can obviate some of the power draw issues of older data centre equipment. Much of the problem comes from the fact that older servers get less performance per watt – “a huge thermal waste,” says Eunice – and were built with the one-application-per-server mindset fostered by the use of Windows and Unix. Many of the old boxes run at 10 to 20 per cent utilization; some are running at as little as two to three.
Shuffle the applications into a virtualized environment, run them on more power-efficient blade servers and slower-clocked but more compute-efficient multicore machines, and there’s a power consumption impact. “Now, we’re getting more workloads onto any given server,” Eunice says
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But you can be too aggressive about using racks full of blade servers in a data centre of older design. Most of these are configured to deliver 3,500 to 4,500 watts per rack. Pack too many blade servers into one rack, and it’s easy to overshoot that mark.
“In some cases, it doesn’t really have to be blades,” Eunice says. The goal is more modularity and efficiency. “Sometimes, blades can come in as the physical form of that modularity.”