Years ago, data center managers didn’t think a whole lot about power expenditures. They were just a cost of doing business. But today, power expenditures have grown to the point that they are overwhelming IT budgets. Just how bad has it gotten? An IDC study conducted in Europe found that the cost of powering data centers now exceeds the costs of acquiring new networking hardware or new external disk storage.
So let’s talk about five steps you can take to corral runaway power costs.
1. Dynamic power capping. With some workloads you can cap power without sacrificing performance. This might save you up to 20 watts per server. Power capping tends to work best with I/O intensive workloads, where CPUs spend a lot of time waiting for data. We’ve seen outstanding results with IT organizations that take a workload-centric approach to power capping.
2. Dynamic workload power distribution. When you have servers that not fully loaded you have the opportunity to shift virtualized workloads off of some servers, which can be put in a low-power state until they are called back into service. VMware’s Dynamic Power Management tool is the tip of the iceberg on this model.
3. Power capping to increase data center density. When server racks are under-populated, you’re probably paying for power capacity that you aren’t using. Intelligent power node management allows you to throttle system and rack power based on expected workloads and put more servers per rack.
4. Optimized server platforms. Optimized server platforms can give you more bang for your energy buck. Here’s one example: When cores within a CPU are idling, they are still drinking up power. Integrated power gates on processors allow idling cores to drop to near-zero power consumption.
5. Solid state drives. Today, lots of people are talking about performance gains with solid state drives. But that’s only part of the story. In addition to performance benefits, solid state drives can save you a bundle on power when compared to standard hard-disk drives.
And those runaway power costs we were talking about? Let’s go rope them in.
 “Server Power Consumption Stabilizes in Europe, But Energy Costs Keep Booming, Says IDC.” IDC news release, Oct. 16, 2009.