I. Introduction
Several major Information and Communication Technology (ICT) companies, such as Amazon, Google, Microsoft, and Facebook, are operating large-scale data centers around the world to handle the ever-increasing cloud infrastructure demand. However, the growing demand has considerably increased the energy consumption of the cloud data centers [1]. High energy consumption not only translates to a higher cost, but also leads to higher carbon emissions. Therefore, energy-related costs have become a major economical factor for data centers and research communities are being challenged to find efficient energy-aware resource management strategies. Moreover, achieving the desired level of Quality of Service (QoS) between cloud providers and their customers is critical in a data center. The QoS requirements are formalized via Service Level Agreements (SLAs) that describe the required characteristics, such as minimal throughput and maximal response time or latency of the system.