Tom Keller, who leads the Power Aware computing group at IBM's Austin Research Lab, gave a talk at the monthly Austin Forum on the problems and emerging solutions surrounding power consumption in data centers, the engines of net traffic, search, and commercial transactions. Highlights:
- Across the nation, there are around 10 million servers in 10 thousand data centers.
- In year 2005, estimates of the fraction of overall power used nationwide by data servers range from 1.2 (just the computers) to 2% (including cooling and other infrastructure). By 2010 this figure is projected to increase 40-70%.
- In Austin, 2.5% of Austin Energy's power is used for standalone data centers. This is projected to increase to 10% of Austin's power usage. This figure does not include mixed use sites (like IBM, where thousands of servers and workstations are employed for simulation and design tasks).
- One server rack consumes the power equivalent of 13 average Dallas homes (15 average California homes): 20-25KW
- If present trends continue, the lifetime energy costs to run a server will soon exceed the cost of the server.
- Many regions and municipalities are tapped out, and really can't support expansion. Difficulties in California led to an explosion of data centers in the Pacific Northwest, which is now threatening to saturate the available hydro based power system. New data center proposals in New York City are meeting with resistance from utilities.
- Newer processor designs since 2004 have decreased the rate of growth in power usage. Some communities (California's Pacific Gas and Electric) have instituted rebate programs to replace servers with more efficient models. Austin Energy was said to be considering a program modeled on the one pioneered at PG&E. (See this Q&A with the PG&E data center market manager.)
- Virtualization, in concert with more efficient designs, can consolidate applications onto one heavily utilized high computer per watt server running emulators of the replaced systems.
- Software efficiency gains could reduce wasted power. However, today, the typical Intel-Windows machine runs at about 10% CPU utilization, with the rest going to waste.
- A surprising amount of waste is due to obsolete servers, applications, and storage devices which are not identified until a data center move. After a move, Tom says anecdotal evidence suggests 20-30% of machines are taken offline. Typically the daily grind in a big data center prevents the discovery of such moves, but research is in progress to assist with this.









