Servers are the new SUVs

According to a new AMD-commissioned study, most servers are more power hungry now than they were in 2000. But what does that mean for the future? This morning I put that question to Jonathan Koomey, the author of Estimating Total Power Consumption by Servers in the U.S. and the World, released today.

According to Koomey, a staff scientist at Lawrence Berkeley National Laboratory and consulting professor at Stanford University, both the number of servers in use and the energy consumed by those servers in U.S. data centers doubled between 2000 and 2005. The typical server in 2007 delivers much more performance than does its 2000 predecessor, but energy efficiency is no better. In fact, while it would appear that overall efficiency per server has remained flat, it's actually worse.

Koomey's report aggregates data on high-performance, mid-range and volume x86 servers using installed base numbers provided by IDC. While the average energy consumption per server remained flat for all servers as a group, power consumption for volume servers - which represents the largest and fastest growing segment and account for the lion's share of the power consumed - actually went up. A drop in energy consumption by mid-range systems compensated for that rise, obscuring that fact somewhat in Koomey's report.

No wonder things are heating up in the data center. While volume servers are more efficient than ever from a performance standpoint, average power consumption per server is actually higher than it was in 2000 - and we have more servers than ever. "Unless some serious efforts are undertaken, power consumption will continue to increase further," Koomey warns.

Will that trend continue? There are some mitigating factors. For one thing, growth of server unit sales dropped from double digits two years ago to single digits last year and may go to zero in 2007, according to IDC. This is due in no small part to data center consolidation projects that exploit increased performance per server, multi-core designs and the use of virtualization technologies. But that's only a temporary phenomenon. Once consolidations are completed, the number of virtual servers - and the physical servers underneath them - will continue to steadily climb.

AMD says it will continue to provide performance increases within the same power envelope. That said, servers supporting virtual machines may be getting fatter, accommodating huge amounts of on-board memory and other supporting components (see Inside scoop from IDC: Sun blades rising, server sales flat, eight core on hold). While processor power might remain flat, it's likely (all things being equal) that overall per-server power consumption will continue to trend upwards. And as prices of servers and virtual servers continue to drop and users discover the ease with which virtual servers can be deployed, the number of servers/virtual servers in use is likely to continue its upward surge.

The EPA is already working on "fuel economy" ratings for servers. When those metrics arrive, will the servers perform more like a Honda Civic - or a General Motors Hummer? Unless something changes, volume servers will cement their reputation as the Kilowatt-guzzling SUVs of the data center.