Authors (if Research)
Ludmila Cherkasova, Diwaker Gupta, Amin Vahdat
Perfomance Evaluation Review. Vol 35, Number 2. Sept 3, 2007
The primary motivation for enterprises to adopt virtualization technologies
is to create a more agile and dynamic IT infrastructure —
with server consolidation, high resource utilization, the ability to
quickly add and adjust capacity on demand — while lowering total
cost of ownership and responding more effectively to changing
business conditions. However, effective management of virtualized
IT environments introduces new and unique requirements, such as
dynamically resizing and migrating virtual machines (VMs) in response
to changing application demands. Such capacity management
methods should work in conjunction with the underlying resource
management mechanisms. In general, resource multiplexing
and scheduling among virtual machines is poorly understood. CPU
scheduling for virtual machines, for instance, has largely been borrowed
from the process scheduling research in operating systems.
However, it is not clear whether a straight-forward port of process
schedulers to VM schedulers would perform just as well. We use the
open source Xen virtual machine monitor to perform a comparative
evaluation of three different CPU schedulers for virtual machines.
We analyze the impact of the choice of scheduler and its parameters
on application performance, and discuss challenges in estimating the
application resource requirements in virtualized environments.