Multicore and Power Consumption: Ask James About It
Power naps. Now there's something I can relate to. No, not because I get a few minutes of shut-eye in the middle of the afternoon, but because I was just reading about this topic in The Problem of Power Consumption in Servers. The problem, of course, is that data centers are energy hogs, costing money and squander resources.
According to the the U.S. Environmental Protection Agency, the energy consumption of the nation's data centers will exceed 100-billion kWh by 2011, for an annual electricity cost of $7.4 billion. Those figures are about twice what they were in 2006, when data centers already drew more electricity than 5.8-million U.S. households. Data centers waste most of the energy they draw because they must be ready for peak processing demands much higher than the average demand.
Multicore processors provide a means of keeping rampant power usage under control, in part because they're more power efficient than previous generation CPUs. For instance, servers using quadcore Xeon processors can deliver 1.8 teraflops at peak performance using less than 10,000 watts of power, while 1998-era Pentiums would have consumed about 800,000 watts to do the same tasks.
James Reinders recently took time to explain some of this to me. As he pointed out, power consumption in data centers involves more than just the CPU -- there's memory, disk drives, and uniterruptable power supplies (UPS), among other devices, all of which consume a lot of power. What parallelism does is enable a computer to a lot more with less power consumption, and the #1 thing software developers can do to reduce power consumption is to take advantage of parallelism and get the job done faster. The faster you get the job done, the sooner the processor can go into an idle state -- take a power nap, in otherwords -- or move on to other tasks.
There's good a chance that James may be discussing more of these issues in the Go Parallelism! Ease the On-Ramp for C/C++ Windows Development webinar he will be participating in on Tuesday, March 10, 2009 at 9:00 AM PST.
You can attend this event at no charge just by registering here. And if James doesn't talk about power consumption, ask him about it. It really is fascinating stuff.

