Downtime Analysis of Virtual Machine Live Migration
Felix Salfner, Peter Tr, Andreas Polze · 2011
Virtual machine environments like VMware, XEN, KVM, and Hyper-V support live migration of guest operating systems, which is used in data centers to provide uninterrupted service during maintenance or to move computation away from failure-prone hosts. The duration of migration, as well as the virtual machine downtime during this process are essential when assessing if service availability agreements might be violated. We present the result of an experimental study that analyzed virtual machine live migration downtime and duration. We show that total migration time as well as downtime are dominated by specific memory utilization patterns inside the virtualized guest. We experienced that downtime involved by live migration can vary by a factor of more than 23, which can have significant impact on service availability. Keywords-virtual machine, live migration, downtime I. INTRODUCTION