IBM is taking a more holistic approach to cooling its blade servers, letting users pack more powerful servers into...
less space while avoiding overheating in the data center.
At the LinuxWorld conference in San Francisco last month, IBM delivered a crop of new blade servers using Intel's new 64-bit chip. A 64-bit system uses larger amounts of memory and power, which create a new level of thermal and maintenance requirements. This means they get really hot -- more than industry-standard blade servers, which are notorious for their cooling challenges.
IBM said its new 64-bit servers incorporate years of cooling design and engineering technology -- a design it has dubbed Calibrated Vectored Cooling (CVC). Elements of this cooling technology can be found in several IBM servers, including the mainframe. IBM claims blade servers with CVC can run up to 66% cooler than servers without it.
Data center managers are screaming for more compact servers so they can minimize the space that must be dedicated for special IT purposes, said Alex Yost, director of the IBM eSeries, xSeries.
"Over time they want more memory, more drives, and [want to] cram more into that same size package," Yost said. "So there has been this industry-wide effort to get to the greatest possible density while providing the maximum functionality, reliability and manageability -- but they're at odds with the space constraints."
The problem with blade servers, according to experts, is that vendors continue to develop smaller and smaller servers with more computing power. When you pack them into a rack, the servers generate an enormous amount of heat but there's no place for the heat to go. Think of a lot of bodies packed into a small room -- the tighter the squeeze, the hotter it gets.
As a result, how to keep the data center cool is a growing concern among data center managers everywhere and they're scrambling for solutions.
IBM has designed its blade servers so that each of the components (hard drive, memory card, fans) is located in places that minimize the amount of heat. Hard drives, for example, are traditionally in front of the blade box. Memory cards are behind the hard drive, meaning the hard drive is blowing hot air on the memory. Meanwhile, the new blade servers have hard drives and power supplies on one side of the server and processors on the other, with a component that can monitor the temperature and react accordingly. Upshot: Fans blow in the right direction and channel the air through the product in the most efficient way.
Critics contend CVC is nothing more than a design premise and that IBM's release of CVC as a feature is just marketing spin.
Rob Sauerwalt, global brand manager for IBM, agrees CVC is about design -- a design that's absolutely necessary for more efficient cooling.
"CVC is the selection of components in order to keep a balanced design," Sauerwalt said. "I'm not running a cooler processor. I'm dealing with the heat better."
But while IBM may be touting a better design, it's not the only vendor attempting to address the problem.
"IBM is not unique in addressing the blade server cooling problem", said Bob McFarlane, president of the Interport Division at Shen Milson & Wilke Inc., New York. "Talk to most any blade server manufacturer, and one of the first things they'll tout is their cooling design. Some are even designing and building their own special cabinets to maximize air flow and control 'bypass air' -- the heat from the back re-entering the front. And bypass air control is probably as important as the internal air flow design, both of which must be addressed to keep these high-heat chips running at all."
Is IBM doing it better than its competitors?
"That's hard to say," McFarlane said. "There's no objective data on it that I've seen, but they're certainly doing a better job of marketing their CVC solution, even if it is next to impossible to get them to explain what it really means."
Truly solving the heat problem is going to take everyone's innovation, according to McFarlane. This includes chip makers, hardware designers, air conditioning and cabinet manufacturers, mechanical engineers, data center designers and anyone who has to manage the composite result.
Recognizing the problem, Intel now offers its 64-bit Zeon line of extended memory processors with "demand-based switching.," Intel said the processors can reduce power consumption by as much as 30% by automatically sensing processor demand state and reducing clock speed -- a sure way to also reduce power consumption.
"IBM is taking one level of responsibility for improving the cooling problems of the technology they're marketing rather than just handing it to the user and saying good luck," McFarlane said. "But until they publish specs, preferably conforming to ASHRAE 9.9 recommendations, that say 'we can keep our servers operating within spec within an environment that delivers less air and/or at higher temperatures than its competitors,' then as far as I'm concerned it doesn't mean a whole lot beyond marketing."