Energy-aware load dispatching in geographically located Internet data centers

Online service providers (OSPs) have Internet data centers in multiple geographical locations in order to satisfy global user demand. Increased data centers consume a large amount of energy, and at the same time causes increased heat dissipation, greater cooling requirements, reduced computational density, and higher operating costs. It places a heavy burden on both the environment and energy resources. OSPs are now focusing more than ever on the need to improve energy efficiency. A new challenge has emerged besides the energy cost, the reduction of the carbon footprint. Although electricity is a clean and relatively safe form of energy to use, there are environmental impacts associated with the production and transmission of electricity. Meanwhile, increased online services require more Internet usage, especially with the trend of cloud computing; the network costs account for a large portion of operation costs for OSPs. This paper proposes an optimal energy-aware load dispatching model to minimize the electricity and network costs for OSPs. Our model can greatly reduce the costs for OSPs by considering the volatility of electricity market and applying energy-efficiency strategies in each data center. We conduct extensive evaluations based on real workload data and electricity price data. The results prove the effectiveness of our energy-aware load dispatching model with a theoretically guaranteed quality of service (QoS). (c) 2011 Elsevier Inc. All rights reserved.