SLA-Aware and Energy-Efficient VM Consolidation in Cloud Data Centers Using Host State 3rd-Order Markov Chain Model

Virtual machine (VM) consolidation offers a promising approach to saving energy and improving resource utilization in cloud data centers. However, the aggressive consolidation of VMs may lead to Servicelevel agreement (SLA) violations, which are essential for data centers and their users. Therefore, it is essential to find a tradeoff between the reduction in SLA violation level and energy costs. In this paper, we improve and expand our Host state 3rd-order Markov chain (HS3MC) model proposed in our previous research comprehensively: we propose a new VM selection algorithm, an improved VM placement algorithm, and an HS3MC-based VM consolidation algorithm based on our improved HS3MC model for the SLA-aware and energy-efficient consolidation of VMs in cloud data centers. We evaluate our proposed algorithms on an extended Cloudsim simulator using the PlanetLab workload and a random workload. Specifically, we improve and expand the OpenStack Neat experimental platform, and evaluate the performance of our algorithms in a real cloud environment based on OpenStack. The experimental results show that our proposed model can significantly reduce the SLA violation rates while maintaining energy efficiency.