Re: Credit-Based CPU Scheduling & Modifying VM Disk Size

["Daniel P. Berrange" <berrange@redhat.com>]

On Mon, Aug 09, 2010 at 04:33:46PM -0400, Michael Li wrote:
> Just wondering if KVM supports (if not now then will it in future releases) the following:
> 
> - Credit-Based CPU Scheduling like Xen. I tried the following command using RHEL 5.5 and it does not work:
> 
> $ virsh schedinfo RHEL5u3-tomcat
> Scheduler      : Unknown
> error: this function is not supported by the hypervisor: virDomainGetSchedulerType

libvirt only supports the schedinfo command / API against KVM when you
have the 'cpu' CGroups controller mounted. Cgroups isn't available for
RHEL-5.5 hosts though, so you'd have to wait for RHEL6 in this case.

> - Modify VM's Disk Size

qemu-img can copy disks, resizing as it does it. For raw disks
just dd extra sace onto the end of it (with a suitable seek= param
to avoid killing your existing data :-)

Daniel
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