openstack team mailing list archive

[Eoghan Glynn <eglynn@xxxxxxxxxx>]

Hi Jobin,

As explained earlier, the existing memory and disk.* meters are
not measures of utilization in the classic sense (i.e. the % of an
existing limited resource currently used and available).

If you simply want to know the quantum of memory allocated to the
instance by the hypervisor, then the existing memory meter is fine.

Similarly if all you need to know is ephermal disk size or the rate
of read/write IOPs, then the existing disk.* meters address this.

If on the other hand you want to know how much free memory or unused
diskspace remains available to processes running on the instance, then
this would require new meters as I explained earlier on this thread.

Cheers,
Eoghan


----- Original Message -----
> Thanks Eoghan for your detailed response regarding the current scenario and
> progress related to this project. Had been investigating about this for
> while since they had been documented here in the official ceilometer
> measurements
> page<http://docs.openstack.org/developer/ceilometer/measurements.html>.
> Thanks for your enlightenment!
> 
> 
> On Thu, Jul 18, 2013 at 8:43 PM, Eoghan Glynn <eglynn@xxxxxxxxxx> wrote:
> 
> >
> > Hi Jobin,
> >
> > The memory utilization metering will require a new release of libvirt
> > which will not be available for another few weeks. After that, it will
> > depend on there being developer bandwidth available to put the ceilometer
> > support in place for a new meter type.
> >
> > We have no current plans that I'm aware of to implement metering of disk
> > utilization (in the sense of available diskspace, equivalent to that
> > reported by say running the df command on the instance). But I could see
> > it being a useful thing.
> >
> > The information is certainly available via the libvirt domain blockInfo,
> > though there may be some wrinkles around multiple block devices versus
> > volumes attached.
> >
> > In any case, please submit[1] a bug with a request for enhancement.
> >
> > Cheers,
> > Eoghan
> >
> > [1] https://bugs.launchpad.net/ceilometer/+filebug
> >
> > ----- Original Message -----
> > > Thanks a lot Eoghan for your detailed response. I have enabled instance
> > > usage auditing in my nova.conf <http://pastebin.ubuntu.com/5887592/>. Is
> > > there anyway I could get these meters(memory and disk utilization) for
> > VM's
> > > provisioned using OpenStack?
> > >
> > > Thanks for your efforts.
> > >
> > >
> > > On Thu, Jul 18, 2013 at 4:57 PM, Eoghan Glynn <eglynn@xxxxxxxxxx> wrote:
> > >
> > > >
> > > > Hey Jobin,
> > > >
> > > > Thanks for your perceptive question.
> > > >
> > > > The reason is that the conduits for gathering CPU metering and memory
> > > > metering are quite different in ceilometer currently:
> > > >
> > > > * cpu/cpu_util are derived by polling the libvirt daemon
> > > >
> > > > * memory is derived from the "compute.instance.exists" notification
> > > >   sent by nova
> > > >
> > > > (This is the pollster versus notification-handler dichotomy you'll
> > > >  see throughout ceilometer).
> > > >
> > > > The reason you're not seeing the memory meter being collected is
> > > > probably because you don't have instance usage auditing enabled in
> > > > your nova config (see the "Configure nova" section in [1]).
> > > >
> > > > However, be warned that this meter is probably not the memory
> > > > utilization statistic that you're expecting. Rather it's likely to
> > > > be a static value reflecting the quantum of memory allocated by the
> > > > hypervisor to the instance (as opposed to the sort of number you'd
> > > > see when running "free -m" on the instance).
> > > >
> > > > I'm looking into adding support for more useful memory utilization
> > > > metering (that could for example drive autoscaling logic), but this
> > > > will require usage of an upcoming release of libvirt.
> > > >
> > > > Cheers,
> > > > Eoghan
> > > >
> > > > [1] http://docs.openstack.org/developer/ceilometer/install/manual.html
> > > >
> > > >
> > > >
> > > > > Hey!
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > > I am running openstack on an Ubuntu 12.04 desktop 64-bit virtual
> > > > machine. I
> > > > > am trying to use ceilometer to get the CPU and memory utilization
> > from my
> > > > > compute node on a KVM host which has a few VM's running on it.
> > > > >
> > > > > However, this is the list of meters I get from ceilometer:
> > > > >
> > > > > cpu, cpu_util, disk.read.bytes, disk.write.bytes, disk.read.requests,
> > > > > disk.write.requests, image, image.size, image.download, instance,
> > > > > instance:m1.small, network.incoming.bytes, network.outgoing.bytes,
> > > > > network.incoming.packets, network.outgoing.packets
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > > Why am I not getting memory usage meters? I don't see the logs to
> > have
> > > > any
> > > > > interpretation of this. Here is my ceilometer config file .
> > > > >
> > > > > --
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > > Thanks and regards,
> > > > >
> > > > > Jobin Raju George
> > > > >
> > > > > Third Year, Information Technology
> > > > >
> > > > > College of Engineering Pune
> > > > >
> > > > > Alternate e-mail: georgejr10.it@xxxxxxxxxx
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > > _______________________________________________
> > > > > Mailing list: https://launchpad.net/~openstack
> > > > > Post to     : openstack@xxxxxxxxxxxxxxxxxxx
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> > > > >
> > > >
> > >
> > >
> > >
> > > --
> > >
> > > Thanks and regards,
> > >
> > > Jobin Raju George
> > >
> > > Third Year, Information Technology
> > >
> > > College of Engineering Pune
> > >
> > > Alternate e-mail: georgejr10.it@xxxxxxxxxx
> > >
> >
> >
> 
> 
> --
> 
> Thanks and regards,
> 
> Jobin Raju George
> 
> Third Year, Information Technology
> 
> College of Engineering Pune
> 
> Alternate e-mail: georgejr10.it@xxxxxxxxxx
>