Energy Star Ratings for Servers, Release 1.0
May 26, 2009 Timothy Prickett Morgan
For the past several years, the Environmental Protection Agency has been working with the server makers of the world to come up with Energy Star ratings–you know, those yellow tags that help you figure out which appliances are energy efficient and therefore save you money over the long run–for servers.
Last week, the EPA rolled out the release 1.0 of the Energy Star for Servers specification, which is the first serious step on the long road to doing green analysis on the gear that goes into data centers. As readers of The Four Hundred well know, I am big on lean, mean, green machines and have been an advocate for using the cheapest computers and consuming the least energy possible when it comes to servers workloads. And Andrew Fanara, the Energy Star product development team leader at EPA, knows that, too, and so I was able to get my hands on the specification package that the server makers got last week.
Considering that getting any of the server makers to agree on anything is a bit like herding cats, it is no surprises to me–or to them–that the release 1.0 of the Energy Star for Server spec has some issues that still need to be worked out. The initial spec basically covers one-way and two-way servers, and does not yet cover larger machines with more processor sockets or blade servers of any size. This is a problem, of course. And it is also a problem that EPA has not yet added networking or storage gear to its Energy Star mission, but one thing at a time. This is Uncle Sam and a resistant (despite all their greenwashing) and cantankerous IT industry we are talking about here.
The EPA is dividing servers into two classes: a standard server; and what it calls a managed server, which means it has a service processor for systems management functions. To get the Energy Star sticker, a single-socket server has to have an idle power draw in a base configuration of 55 watts, or 65 watts if the box has a service processor; for two-socket boxes, it has to idle at 100 watts, and with a service processor it has to idle at 150 watts or less. Each server is expected to have 4 GB of main memory and one disk drive. If a configuration has a redundant power supply, the Energy Star spec allows another 20 watts to be burned, and for richer configurations, you have to add 2 watts per GB of memory and 2 watts per Gigabit Ethernet port; a disk drive is rated at 8 watts. These are the maximum wattages that these components can have to get the Energy Star label slapped on them. The spec also has very precise metrics that the power supplies have to meet to get the Energy Star label.
At some point, EPA will probably slap the SPEC power_ssj2008 benchmark into the spec and test machines under load, which is what you really want to rate a machine. That way, you would have ratings for idle conditions and when the machine is under stress. The EPA didn’t say this was going to happen, but the form that server makers are being asked to fill out to apply for the stickers has SPECpower_ssj2008 ratings in the workload field.
I’ll let you know as machines get certified for the spec and as the spec evolves to include other server types, including midrange and big iron, blade servers, appliance servers, and other gear.