On 10/24/2011 01:50 PM, sethuraman subbiah wrote:
Hi ,
I was previously using xen and currently moved to KVM. I am using libvirt to manage these
VMs. In den's credit scheduler , I had the ability to set a cap on the cpu usage for a
VM. But I was not able to find a similar substitute in KVM. I find that we can use cgroups
to provide shares for VM but that will be more like weight based and it doesn't set a
hard cap for that VM. I tried using cpulimit but I find it inaccurate and we can give
values only between 0-100. Thus, I think it cannot support multi core environments. Can
any one suggest a method to set a hard limit on a VM's cpu usage? Thank you.
Libvirt 0.9.4 added CPU bandwidth limitation support, via <cputune>:
http://libvirt.org/formatdomain.html#elementsCPUTuning. <period> and
<quota> map to hard-coded caps via cgroups, nicer than the weighted
numbers via <shares>.
--
Eric Blake eblake(a)redhat.com +1-801-349-2682
Libvirt virtualization library
http://libvirt.org