ABSTRACT
Green computing is to support personal and business computing needs in a green and sustainable manner, such as minimizing the strain and impact on resources and the environment. Computing systems, particularly enterprise data centers and high-performance cluster systems, consume a significant amount of power. Not only does this increase operational costs, it also places an increasing burden on businesses that generate and distribute energy. For example, the power consumption of enterprise data centers in the U.S. doubled between 2000 and 2005 [1]. In 2005, U.S. data centers consumed 45 billion kW-h; roughly 1.2% of the total amount of United States electricity consumption, resulting in utility bills of $2.7 billion [4]. In 2006, the U.S. Congress passed bills to raise the IT industry’s role in energy and environmental policy to the national level [2]. Furthermore, it is estimated that servers consume 0.5% of the world’s total electricity, which if current demand continues, is projected to quadruple by 2010 [42]. The Environmental Protection Agency recently reported that the energy used by data centers by the year 2011 is estimated to cost $7.4B [1]. Some analysts predicted that IT infrastructure will soon cost more on power consuming than the hardware itself [31]. The alarming growth of reducing data center power consumption has led to a surge in research activity.
