Joint Optimization of Server and Network Resource Utilization in Cloud Data Centers.

Virtual machine placement is a key component of cloud resource management, which may affect network bandwidth allocation. In this paper, we revisit the virtual machine placement problem in cloud data centers and aim to maximize the overall resource utilization in multiple dimensions, while ensuring that the resource constraints on both the server such as CPU capacity and the network such as bandwidth are not violated. We model the bandwidth-guaranteed virtual machine placement problem and prove its NP-hardness, and design offline and online algorithms to solve the problem. We first consider the offline version and develop approximation algorithms with bounded performance ratios for both the homogeneous and the heterogeneous cases. Then, for the online version, we propose simple and efficient heuristics based on the insights from the offline algorithm design. Comprehensive experimental results verify that the overall resource utilization can be significantly improved by applying our proposals.