6. Power Issues in Servers and Data Centers

Power optimization as a research topic was first studied in the context of portable and handheld systems where saving battery life was of prime importance. However, since that time, the need for saving power has become significantly more pervasive all over the computing machinery, from portable devices to high-end servers and data centers. The need for power optimization in larger scale computing environments such as servers and data centers arise from the increasing maintenance costs (including the electricity charges) due to the power demands of a very large number of computers. This introduces new contradicting requirements in the server design space, which, in the past, were designed to a different set of specifications. Performance was the primary design metric, with execution time and throughput being the main considerations. In addition, reliability and fault-tolerance related concerns were also significant, leading to designs with redundancy that offered high availability. While these concerns continue to be important, the emergence of power efficiency has led to interesting innovations in the way such systems are conceived, architected, and programmed.