Authors (if Research)
Christopher Clark, Keir Fraser, Steven Hand, Jacob Gorm Hansen, Eric Jul, Christian Limpach, Ian Pratt, Andrew Warfield
Published at NSDI 2005
Migrating operating system instances across distinct physical
hosts is a useful tool for administrators of data centers
and clusters: It allows a clean separation between hardware
and software, and facilitates fault management, load
balancing, and low-level system maintenance.
By carrying out the majority of migration while OSes continue
to run, we achieve impressive performance with minimal
service downtimes; we demonstrate the migration of
entire OS instances on a commodity cluster, recording service
downtimes as low as 60ms. We show that that our
performance is sufcient to make live migration a practical
tool even for servers running interactive loads.
In this paper we consider the design options for migrating
OSes running services with liveness constraints, focusing
on data center and cluster environments. We introduce
and analyze the concept of writable working set, and
present the design, implementation and evaluation of highperformance
OS migration built on top of the Xen VMM.