Sun Microsystems has really upped the ante when it comes to cutting the power draw of modern servers. The new Sparc Enterprise T5440, co-developed with Fujitsu, incorporates just about every power-saving trick in the book -- a design that costs more up front but which Sun says can pay for itself within a year of operation.
Top of the list is intelligent fan control. Rather than just running fans constantly to maintain a steady air flow, the T5440 can adjust fan speeds and can identify different cooling zones within the box so it uses only the fans closest to heated components.
Other techniques include digitally routed power distribution and something called "thread parking," which funnels threads into a minimum number of cores and shuts down those that aren't needed.
Controlling consumption on the CPU will be one of the "hot" (sorry) trends in data center energy management over the next decade, according to this editorial in Processor. As things get more virtualized, improved idling methods and other means to ensure that only necessary resources are being used will start to take center stage.
Gradually replacing existing servers with new high-efficiency models is all well and good, but many data centers are struggling with energy costs now. Is there a way to retrofit today's server farms to help the electric meter run a little slower?
A number of startups are doing just that. One company called Rittal offers what it called the Liquid Cooling Package Inline system that can be retrofitted into existing server architectures, even ones without raised floors. The 300mm wide system rests inside the server rack rows and provides a maximum air flow rate of 4,600 m3/h. The system also has remote management software that monitors flow and return temperatures, fan speed, inlet and outlet temperature and other parameters.
Emerson Network Power has developed what some are calling a "server fridge" but can be more accurately described as an air-conditioned rack. The Liebert MCR (Mini Computer Room) allows you to cool only the encased server enclosure, rather than the entire room. It also provides constant cooling, unlike traditional systems to power up and down at regular intervals.
Energy prices may not be as high as they were this past summer, but it would be foolish to think that the good ol' days are here again. Even if declining costs mean the ROI on energy efficieny is a little farther off than you expected, it still beats the alternative.