Server Operational Cost Optimization for Cloud Computing Service Providers over a Time Horizon

Service providers are migrating to on-demand cloud computing services to unburden the task of managing infrastructure, while cloud computing providers expand the number of servers in their data centers because of the increase in load. With this growing need, their energy consumption increases significantly. Conserving energy and reducing the operational cost while satisfying the service level agreement (SLA) becomes important in order to reduce both carbon emissions and the budget for cloud computing providers. On the other hand, the aggregated demands for different services are dynamic over a time horizon. We present a multi-time period optimization model for saving the operational cost by combining two factors: 1)Dynamic Voltage/Frequency Scaling (DVFS), 2)turning servers on/off over a time horizon. We show the impact of the granularity of the duration of the time slots and frequency options on optimal solutions. A parametric study on varying cost of turning servers on/off and power consumption is also presented. 1