Too Hot to Handle?By Brian P. Watson | Posted 2006-09-07 Email Print
These boxes offer a compact, powerful alternative to traditional rack-mount servers. But they bring along a new set of concerns to address.
Too Hot to Handle?
Moving ahead, vendors will have to continue to make blade server systems more power-efficient, customers say. An individual blade server requires less electricity than a single rack-mount server, but with about twice as many servers in a rack, the power requirement goes up. Leading vendors have unveiled server products with lower-powered chips, which perform as well as other blade servers but burn through less wattage.
When blades first emerged, customers figured increased server density would lead to more heat production. More heat meant adding more air conditioning to the data center—and that could be a significant cost, many believed, especially if those facilities weren't wired to handle the higher power requirements. "It's forced people to change the way they think about wiring up their data center," says Eric Vishria, vice president of marketing for Opsware, a server management software maker.
In 2005, the average number of servers per rack was 14, according to IDC. The firm expects that number to jump to 20 per rack by 2010, adding increased power density to data centers. That, coupled with fluctuating energy costs, makes power and cooling budgets even harder to predict, blade users say.
To a degree, Houghton International had planned ahead. The Valley Forge, Pa., industrial lubricant maker had a 100-square-foot computing room with 20 tons of air-conditioning capacity—which requires just over 70 kilowatts—per day.
Trimming that capacity became a top priority in 2001 as Houghton bought the first generation of Dell blade servers, the PowerEdge 1655, to split applications onto multiple servers and boost disk utilization and memory bandwidth, according to chief technologist Clarke Thomas.
His blades, which take up about 30 square feet of the 100-square-foot room, currently use about 15 kilowatts per day, which Thomas says cut the cooling need to about five tons.
Since power usage and heat output can change based on a server's workload, Thomas says, the company is looking into an eight-ton cooling unit and adding two more units for failover capabilities. "A/C costs should be something every party buying blades [needs] to review," Thomas points out.
Besides power and cooling, some users say standards and interoperability represent another issue. Customers like Jeff Pelot, chief technology officer at the nonprofit Denver Health Hospital, say vendors need to make their standards "as ubiquitous as possible."
Pelot deployed IBM blades to consolidate data center space. His team was certified to manage Cisco switches—which route data from the blades to one of the company's networks—but the IBM BladeCenter switch was proprietary. "This would have added a layer of complexity that I couldn't have supported without more training or outside help," Pelot says. So instead of using the built-in switch, he says he paid $9,000 for two four-port switches from Cisco, which were optional through IBM.
Pelot says he learned a valuable lesson from that experience: Today, he lists the hospital's standards on every request for proposal he and his team send out. "If the vendors can't adhere to that," he says, "they'll have a hard time getting in."
Blade Servers: Slicing and Dicing
WHAT IT IS:Individual circuit boards with processors and network connections packed into smaller boxes than rack-mount servers. Blade servers sit in an enclosure that provides power, cooling and network connections, and most blades are "hot-swappable," meaning they can be taken out and replaced while systems continue to operate.
WHAT'S HAPPENING:Companies turned to blade servers to consolidate space in their data centers and speed up the provisioning of servers. Blades pack more processing power into a small form factor compared to rack-mounted servers, yet require more electricity to operate and more energy to cool because they emit more heat.
MARKET SIZE: $2.2 billion, blade servers worldwide in 2005 (IDC).