On Strategies for Dynamic Resource Management in Virtualized Server Environments

Virtualization rapidly gains popularity affecting multiple levels of the computing stack. Since it decouples resources from their users it provides greater flexibility in terms of resource allocation but also brings new challenges for optimal design, provisioning, and runtime management of systems. This paper presents an analytical model of virtual machine migration that provides an estimate of the expected improvement in response time due to a migration decision. The model explicitly accounts for predictability of resource demands and characteristics of the virtualization infrastructure, such as migration time and overhead. It brings new insights into the decision strategies that should be used to improve the overall responsiveness of the system when dynamically managing virtual machines. The model is validated using simulations driven by data center resource utilization traces.