The U.S. Environmental Protection Agency this week released the third draft of the Energy Star 2.0 specification for servers, which is expected to be finalized on Nov. 9.
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The specification is expected to be implemented in servers on Aug. 13 next year, according to the draft specification documents. The new specification is the successor to Energy Star 1.0 for servers that went into effect in May 2009. Companies such as Hewlett-Packard, Dell and IBM offer servers that qualify under the Energy Star 1.0 specification guidelines.
The Energy Star program is widely used in PCs, monitors, light bulbs, refrigerators and dozens of other products, with servers being a recent addition. The Energy Star specification rates power-efficient products and helps customers make effective purchase decisions. Products are typically identified with an Energy Star label.
The first version of Energy Star for servers that went into effect in 2009 took basic rack and tower server configurations into account, and set up guidelines for future specifications. The Energy Star 2.0 specification currently under consideration covers server types and processor technologies not considered in the first specification.
For example, Energy Star 2.0 now covers blade servers, which were left out of the first version due to the complexity involved in defining the configuration of blades, which are highly scalable depending on processing needs. The new specification also covers graphics processors (GPUs), which are being increasingly used in data centers to speed up math and scientific tasks. GPUs were not prominent in servers at the time of the Energy Star 1.0 specification, and now some of the world's fastest computers deploy clusters that combine CPUs with GPUs for fast task execution. Also being taken into account in the new Energy Star specification are the power-efficiency attributes of storage systems inside servers.
Server architecture has also been changing over the years, with many server vendors installing proprietary technology to manage, monitor and cap server power usage. HP, for example, has installed sensors and embedded hardware in its latest Proliant Gen8 servers to identify overutilized servers based on location, power, workload and temperature data. System administrators can redirect workloads from overutilized servers to other systems to ensure data centers are operating at peak efficiency. Dell has also implemented similar technology in its new PowerEdge servers.
Energy Star for servers could be important given that servers are progressively consuming more of the nation's power, and given that half of the data center costs are tied to power and cooling, said Nathan Brookwood, principal analyst for Insight 64.
"It's setting standards and helping people understand what power requirements are," Brookwood said. "The more you can do to nudge people to be sensitive in power efficiency is better for customers and country as a whole."
Enterprises are looking to squeak out maximum performance from servers based on workloads and time of the day, Brookwood said. Hardware is becoming more power efficient, but enterprises are also trying to keep power consumption low when the servers are idle.
"There may be times when they are not doing a lot, you don't want them using power," Brookwood said.
There has been a growing interest in buying low-power servers, and Energy Star could guide companies in the right direction, Brookwood said. Cloud companies like Facebook and Google buy servers in volume to boost performance while lowering power costs. There also is a growing interest in low-power ARM processors, which are used widely in smartphones and tablets, as an alternative to the more power-hungry x86 processors from Intel and Advanced Micro Devices, which are used in most data centers.
There is a need for standardized ways to measure power, but servers are different as the metrics are too vast to put under a single measure, said Dan Olds, principal analyst at Gabriel Consulting Group.
Energy Star works well with air conditioners and dishwashers because those appliances do simple things, and it is easy to measure power consumption and assign a score to it. Server behavior is complex and workloads are based on different attributes, making it difficult to apply a specific metric to determine power consumption.
"An application that is CPU dependent will use power at a different rate than an application that is doing Web surfing and sending out traffic over a network," Olds said.
EPA is working with top server makers and nonprofits to come up with Energy Star 2.0, and are fully capable of coming up with a standard, Olds said. But there are too many considerations to take into account with servers and the standard could end up being deceptive, Olds said.
The idle power limit in Energy Star 2.0 for servers has been set at between 47 watts and 57 watts for one-socket servers and between 92 watts and 142 watts for two-socket servers, less than limits set in the Energy Star 1.0 specification. An additional power allowance is given when components are added: for example, an extra hard drive gets eight watts of power, while additional RAM exceeding 4GB gets 0.75 watts of power per gigabyte. Power supplies are assigned 20 watts of power per unit.
The new specification does not consider high-performance computer systems, fault-tolerant servers or server appliances, which are typically used for specific tasks such as storage or networking.