Green scheduling for cloud data centers using ESDs to store renewable energy
Chonglin Gu, Hejiao Huang, Xiaohua Jia · 2016
In this paper, we study the issues of scheduling of user requests to geographically distributed data centers. The data centers are powered by three types of energy: wind, solar, and brown energy. We consider using energy storage devices (ESDs) to store energy when its supply is abundant or the price is low, and discharge it when the energy supply is in short or expensive. By introducing ESDs in data centers, it brings some new challenges regarding the scheduling of user requests, such as when and how much to charge the energy into ESDs and when to discharge it, how this charge and discharge of ESDs affects the QoS and total energy cost. We focus on two optimization problems: 1) Schedule the servers and energy usage from different energy sources, such that the QoS requirement is met and the total energy cost is minimized. 2) Minimize total carbon emissions for given a budget of energy cost. The problems are formulated as mixed integer linear programming problem (MILP). We use Cplex to solve the formulated problems. We have run extensive experiments on traces from real world. Experiments show that our scheduling methods using ESDs can significantly reduce both carbon emissions and total cost.