Date Added: Sep 2011
Power consumption imposes a significant cost for implementing cloud services, yet much of that power is used to maintain excess service capacity during periods of low load. In this paper, the authors study how to avoid such waste via an online dynamic capacity provisioning. They overview recent results showing that the optimal offline algorithm for dynamic capacity provisioning has a simple structure when viewed in reverse time, and this structure can be exploited to develop a new 'Lazy' online algorithm which is 3-competitive. Additionally, they analyze the performance of the more traditional approach of receding horizon control and introduce a new variant with a significantly improved worst-case performance guarantee.