[ovirt-users] Resource Pools in oVirt

[Doron Fediuck]

----- Original Message -----
> From: "s k" <sokratis123k at outlook.com>
> To: "Doron Fediuck" <dfediuck at redhat.com>
> Cc: users at ovirt.org, "Michal Skrivanek" <mskrivan at redhat.com>
> Sent: Saturday, June 14, 2014 1:33:26 PM
> Subject: RE: [ovirt-users] Resource Pools in oVirt
> 
> That's great Doron! Especially the QoS Policy sounds almost like the VMware
> Resource Pools.  Looking forward for the next release then!

Actually I'd expect a better implementation as we hand aspects which
are not available in Resource Pools.

> By the way, since we are talking about CPU shares, the default option when
> creating a VM is 'disabled'. How is that compared with the Low/Medium/High
> options in terms of CPU priority?
>

According to the docs[1]:
"If this is omitted, it defaults to the OS provided defaults."

I guess it would be interesting to check this while it's running to get
the actual number from your run.

Doron

[1] http://libvirt.org/formatdomain.html#elementsCPUTuning


> > Date: Fri, 13 Jun 2014 04:29:09 -0400
> > From: dfediuck at redhat.com
> > To: sokratis123k at outlook.com
> > CC: users at ovirt.org; mskrivan at redhat.com
> > Subject: Re: [ovirt-users] Resource Pools in oVirt
> > 
> > ----- Original Message -----
> > > From: "s k" <sokratis123k at outlook.com>
> > > To: users at ovirt.org
> > > Sent: Wednesday, June 11, 2014 12:18:35 AM
> > > Subject: [ovirt-users] Resource Pools in oVirt
> > > 
> > > Hello all,
> > > 
> > > As far as I understand, CPU Shares can be set on each VM individually and
> > > cannot be changed while it's powered on.
> > > 
> > > 
> > > It would be great if we could create resource pools (similar to what
> > > VMware
> > > does) for CPU shares so that we could assign priorities on multiple VMs
> > > and
> > > be able to move them between Resource Pools of different priorities. I
> > > know
> > > that we can configure quotas but it's not the same as CPU shares.
> > > 
> > > Is that something planned for a future release? Shall I open an RFE for
> > > that
> > > ?
> > > 
> > > Regards,
> > > 
> > > Sokratis
> > > 
> > 
> > Hi Sokratis,
> > thanks for the feedback.
> > 
> > We have an RFE[1] opened to allow changing shares dynamically for a VM
> > while it's
> > running.
> > 
> > As you probably know VMWare's implementation handles much more than shares,
> > so
> > it's a wider concept.
> > 
> > In oVirt we've been working hard to introduce QoS elements during 3.3 and
> > 3.5
> > versions[2]. Once we have it all in place we'll start heading for the next
> > level
> > (up) which will be a Policy to aggregate QoS aspects for a VM. Once we have
> > a
> > policy you'll be able to assign it to multiple VMs and have much better
> > control
> > over resource including a planning element. So you should be monitoring the
> > Policy
> > task progress once we start working on it.
> > 
> > So... as you can understand this is a lot of work (which I'm sure was the
> > same
> > for VMWare when they did it). Until then you'll be able to handle it using
> > [1]
> > I expect to happen in the next version, and as always- patches are
> > welcomed!
> > 
> > Thanks,
> > Doron
> > 
> > [1] Bug 1103537 - [RFE] Dynamic CPU Shares
> > [2] QoS aspects:
> > http://www.ovirt.org/Features/CPU_SLA
> > http://www.ovirt.org/Features/Network_QoS
> > http://www.ovirt.org/Features/blkio-support
>