Virtualization no cure-all for data center energy crunch
- 19 July, 2010 06:10
Virtualization gave data center managers some breathing room in their battle against rising energy use, but more changes are needed to keep pace with the demands of IT departments, speakers at an industry conference said Friday.
Those changes include tighter integration between IT equipment and building management systems -- so that temperature readings from servers can be used to directly control cooling systems, for example -- and better communication between IT staff and the facilities teams that run the data center.
Many data centers are approaching the limits of their power and cooling capacity, and data center managers are looking for creative ways to do more with the infrastructure they have. Energy costs have also been rising and carbon legislation looms, so corporate executives are putting pressure on their data centers to get in shape.
Virtualization was seen as one solution to the energy crisis, because it can improve server utilization and reduce the number of systems in use. It has helped a little, but it hasn't stemmed the relentless increase in demand for more computers and more energy, according to speakers at the Datacenter Dynamics conference in San Francisco.
"For our clients, virtualization was perceived as a solution to all the ills, but what we've seen over the past few years is not a slowdown in growth. If anything, we see companies asking how they can get more kilowatts -- today," said Gary Brennen, co-CEO of data center construction company Syska Hennessy.
"The appetite for new apps is outpacing any technology solutions that are coming to bare," he said.
Steven Press, executive director for data center facilities at health insurance giant Kaiser Permanente, agreed that virtualization is no panacea. "It's one of many tools we have to curtail growth and energy consumption, but I don't see it as the be all and end all."
"I'd put more of a stake into what we're going to see in future server designs, in more efficient computers that allow us to virtualize more with less energy consumption," he said.
In some scenarios, virtualization can actually increase demand for power and cooling, the panelists said. Technologies like VMware's vMotion, for example, allow companies to move a running workload from one pool of servers to another, creating an on-demand computing environment.
"But there's an issue we're all ignoring: If you move a big block of compute from one place to another, what follows it? The electrical and thermal load," said Rob Aldrich, principal solutions architect at Cisco Systems.
The power and cooling have to be in place at the location where the workload was moved from as well as at the destination, he said. Most data centers can't adjust that power and cooling supply -- the so-called environmentals -- in synch with the workloads as they move back and forth, creating inefficiencies.
"We've all been talking about computing-on-demand, but we haven't talked about environmentals-on-demand," Press said. "We have to get more granular on our ability to control power distribution and [cooling] at the cabinet level if we're going to be able to model that computing-on-demand pattern."
The key to that, the panelists said, is connecting building management systems to the IT network, so that power and cooling systems can be turned up and down in real time to match the requirements of the IT equipment.
That's hard today, because building control and IT networks use different communication protocols. "Facilities today tend to be very reactive -- we haven't seen the same degree of IP enablement as you have in IT," Aldrich said. "If you look at how we manage environmentals for facilities, it really hasn't changed much since the '70s. There's no full convergence of these critical systems."
There are projects, including one led by the Lawrence Berkeley National Laboratory, to bring the building control and IT networks together, so that information taken directly from servers -- such as temperature, CPU utilization and fan speed -- can be used to control cooling systems directly.
"If we marry those two networks, the servers can control the building fans and air conditioning to give them exactly what they need," said Bill Tschudi, a program manager at Lawrence Berkeley.
It's not just a technical problem, however. The key is getting facilities staff, IT staff and corporate executives to tackle the problem together, said Eric Adrian, an executive vice president with Jones Lang LaSalle, which manages data centers for Bank of America. "You need a holistic approach," he said.
Press of Kaiser Permanente agreed. "We're going to have to work harder with our IT brothers and sisters and come together as a cohesive team."
But for him, the responsibility to get things moving lies with those who run the data centers.
"We build data centers to support the IT department; to them it's just a utility," he said. "We have to make them understand -- it's our responsibility to educate them."