EPA to Start Small on Energy Star for Servers

Computerworld - This version of this story originally appeared in Computerworld's print edition.

The U.S. Environmental Protection Agency expects to introduce its first Energy Star rating for servers by year's end, though a more comprehensive system that measures the energy consumed by actual workloads will take longer to develop.

The Energy Star program is designed to make it easier for customers to compare the energy efficiency of different products. Ratings are available for more than 50 types of products, including desktop PCs, monitors, ceiling fans and even windows. But the server rating system has been difficult to develop.

"This server program is one of the most complicated we've tried to deal with," said Arthur Howard, an associate at ICF International Inc., a Fairfax, Va., firm that provides technical consulting to the EPA on the Energy Star initiative.

That's partly because servers are used for so many different workloads. Hardware makers say a benchmark test that measures energy efficiency on one type of workload, such as file serving, won't provide meaningful results to buyers looking to use systems for other applications, such as transaction processing.

After Congress pushed the EPA to promote the adoption of more energy-efficient servers in 2006, the agency quickly determined that it wouldn't be able to get server vendors to agree anytime soon on a way to measure the "useful work" a system can perform with a given amount of power, said Andrew Fanara, who heads the Energy Star product development team at the EPA.

The EPA hopes to use energy efficiency tests developed by Standard Performance Evaluation Corp., a nonprofit company that creates performance benchmarks for servers. Thus far, though, SPEC has published only one test suite, for measuring the energy consumed by servers running a Java-based application workload. The group hasn't said when it will add benchmarks for other types of workloads.

The EPA decided to sidestep the issue and come up with an initial "Tier 1" rating system for two key areas it thinks can be measured. One is the efficiency of a server's power supply, as measured at various load levels; the other is how much power a server consumes while it's idle.

But the EPA may have its work cut out for it, even on the Tier 1 spec. For example, Mark Monroe, director of sustainable computing at Sun Microsystems Inc., posed a question that has yet to be answered: "What's the definition of idle?"

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