Cost of Virtual Machine Live Migration in Clouds: A Performance Evaluation

TL;DR

This paper evaluates the performance impact of live virtual machine migration in cloud data centers, highlighting acceptable overhead levels and implications for SLA compliance in Web 2.0 applications.

Contribution

It provides an empirical analysis of live migration effects on application performance within Xen VMs, focusing on Web 2.0 workloads.

Findings

Migration overhead is generally acceptable

Performance impact can affect SLA compliance

High potential for live migration in modern data centers

Abstract

Virtualization has become commonplace in modern data centers, often referred as "computing clouds". The capability of virtual machine live migration brings benefits such as improved performance, manageability and fault tolerance, while allowing workload movement with a short service downtime. However, service levels of applications are likely to be negatively affected during a live migration. For this reason, a better understanding of its effects on system performance is desirable. In this paper, we evaluate the effects of live migration of virtual machines on the performance of applications running inside Xen VMs. Results show that, in most cases, migration overhead is acceptable but cannot be disregarded, especially in systems where availability and responsiveness are governed by strict Service Level Agreements. Despite that, there is a high potential for live migration applicability in data centers serving modernInternet applications. Our results are based on a workload covering the domain of multi-tier Web 2.0 applications.