Nice:Network-aware VM Consolidation Scheme For Energy Conservation In Data Centers

Energy conservation and network performance have become two of the most important issues in data center as the scale of cloud services continues growing.Recent researches usually consider these two issues separately. Energy conservation mainly deals with hosts, which reduces total energy consumption by consolidating virtual machine(VM)s to fewer hosts, and network performance mainly deals with network scalability and energy e?ciency, which improves data center network(DCN) scalability by applying new network topologies or routing schemes and improves DCN energy e?ciency by consolidating tra?c and dynamic DCN.However, it is obvious that VM consolidation affects tra?c distribution in DCN, and tra?c distribution is directly related to the scalability and energy saving potential of DCN. Therefore, we propose to reduce host energy consumption and to improve DCN scalability and energy e?ciency at the same time through VM consolidation. Since the scalability of DCn is the bottleneck of data center scalability, in this way, we can improve energy e?ciency and scalability of data center at the same time.Therefore, we propose to improve network performance while reducing energy consumption in data center. In this paper, we don’t negelect VM migration cost. In order to analyse VM migration cost quantatively, we precisely measure VM migration cost through real-trace experiments in a 6-server testbed via VMware and we define migration cost based on the experiment results. We also define the cost functions for host and network tra?c. Based on these cost functions we define Combined VM Consolidation(CVC) problem. Then, We prove that CVC is NP-complete and is inapproximable by a factor of 3/2- ε unless P = NP.Next, we propose NICE: Network-aware VM ConsolIdation scheme for Energy Conservation in Data CEnter to solve CVC. NICE consists of three subroutines,i,e, FirstFit-Decr, Kernighan-Lin, and Greedy-Map. Massive simulations validate the e?ciency of NICE. In all, to the best of our knowledge, we are the first work to combine VM consolidation with network optimization and migration cost.