2:21 a.m.
Hi everybody,
I'm using the PHP API to make a web interface interact with the virtual
machines installed on some hypervisor.
Everything is fine, but I would like to find a way to get the guest's
cpu and mem usage, so that it should be possible to make some rrd
graphs. I didn't find out anything and also it seems looking around that
there is no way to obtain those data.
What is strange for me is that programs like virt-top are showing
exactly what I'm looking for. Can anyone help me to find out a way to
retrieve those statistics?
Another related question: do you think I can obtain the same data by
using this:
ps aux | egrep "[/]usr/libexec/qemu-kvm.*libvirt.*" | awk '{print
$3"/"$4}'
on the hypervisor? These are related to the kvm process, and the kvm
process IS the virtual machine... Or not?
Thanks to everybody,
--
RaSca
Mia Mamma Usa Linux: Niente è impossibile da capire, se lo spieghi bene!
rasca(a)miamammausalinux.org
http://www.miamammausalinux.org
3:30 a.m.
On Thu, Apr 12, 2012 at 09:21:18AM +0200, RaSca wrote:
Hi everybody,
I'm using the PHP API to make a web interface interact with the virtual
machines installed on some hypervisor.
Everything is fine, but I would like to find a way to get the guest's
cpu and mem usage, so that it should be possible to make some rrd
graphs. I didn't find out anything and also it seems looking around that
there is no way to obtain those data.
What is strange for me is that programs like virt-top are showing
exactly what I'm looking for. Can anyone help me to find out a way to
retrieve those statistics?
virt-top mostly uses the virDomainGetInfo() API to get this data.
Regards,
Daniel
--
|: http://berrange.com -o- http://www.flickr.com/photos/dberrange/ :|
|: http://libvirt.org -o- http://virt-manager.org :|
|: http://autobuild.org -o- http://search.cpan.org/~danberr/ :|
|: http://entangle-photo.org -o- http://live.gnome.org/gtk-vnc :|
3:33 a.m.
Il giorno Gio 12 Apr 2012 10:30:04 CEST, Daniel P. Berrange ha scritto:
On Thu, Apr 12, 2012 at 09:21:18AM +0200, RaSca wrote:
[...]
virt-top mostly uses the virDomainGetInfo() API to get this data.
Regards,
Daniel
Thanks Daniel, since there's no such function in the php api, can you
please help me to find out a solution? Is modifying the libvirt-php
sources the only solution?
Thanks again,
--
RaSca
Mia Mamma Usa Linux: Niente è impossibile da capire, se lo spieghi bene!
rasca(a)miamammausalinux.org
http://www.miamammausalinux.org
3:39 a.m.
On Thu, Apr 12, 2012 at 10:33:41AM +0200, RaSca wrote:
Il giorno Gio 12 Apr 2012 10:30:04 CEST, Daniel P. Berrange ha
scritto:
> On Thu, Apr 12, 2012 at 09:21:18AM +0200, RaSca wrote:
[...]
> virt-top mostly uses the virDomainGetInfo() API to get this data.
> Regards,
> Daniel
Thanks Daniel, since there's no such function in the php api, can you
please help me to find out a solution? Is modifying the libvirt-php
sources the only solution?
Yes, I'd suggest adding it to libvirt-php.
Daniel
--
|: http://berrange.com -o- http://www.flickr.com/photos/dberrange/ :|
|: http://libvirt.org -o- http://virt-manager.org :|
|: http://autobuild.org -o- http://search.cpan.org/~danberr/ :|
|: http://entangle-photo.org -o- http://live.gnome.org/gtk-vnc :|
3:48 a.m.
Il giorno Gio 12 Apr 2012 10:39:42 CEST, Daniel P. Berrange ha scritto:
[...]
Yes, I'd suggest adding it to libvirt-php.
Daniel
But wait Daniel,
as far as I see, the only info I can obtain from virDomainGetInfo are:
unsigned char state : the running state, one of virDomainState
unsigned long maxMem : the maximum memory in KBytes allowed
unsigned long memory : the memory in KBytes used by the domain
unsigned short nrVirtCpu : the number of virtual CPUs for the domain
unsigned long long cpuTime : the CPU time used in nanoseconds
which are *exact* the same data I can reach from the php function
libvirt_domain_get_info. But these are NOT live stats, these does not
contain the actual cpu and memory usage.
So, what you mean when you say that virt-top takes all from
virDomainGetInfo?
--
RaSca
Mia Mamma Usa Linux: Niente è impossibile da capire, se lo spieghi bene!
rasca(a)miamammausalinux.org
http://www.miamammausalinux.org
4:11 a.m.
On Thu, Apr 12, 2012 at 10:48:05AM +0200, RaSca wrote:
Il giorno Gio 12 Apr 2012 10:39:42 CEST, Daniel P. Berrange ha
scritto:
[...]
> Yes, I'd suggest adding it to libvirt-php.
> Daniel
But wait Daniel,
as far as I see, the only info I can obtain from virDomainGetInfo are:
unsigned char state : the running state, one of virDomainState
unsigned long maxMem : the maximum memory in KBytes allowed
unsigned long memory : the memory in KBytes used by the domain
unsigned short nrVirtCpu : the number of virtual CPUs for the domain
unsigned long long cpuTime : the CPU time used in nanoseconds
which are *exact* the same data I can reach from the php function
libvirt_domain_get_info. But these are NOT live stats, these does not
contain the actual cpu and memory usage.
Err, yes they are the live stats. 'memory' shows the current memory
consumed by the VM, while 'cpuTime' shows the absolute CPU time
consumed since boot. To get % CPU time, take two readings 'n' seconds
apart and calculate the delta between them
Daniel
--
|: http://berrange.com -o- http://www.flickr.com/photos/dberrange/ :|
|: http://libvirt.org -o- http://virt-manager.org :|
|: http://autobuild.org -o- http://search.cpan.org/~danberr/ :|
|: http://entangle-photo.org -o- http://live.gnome.org/gtk-vnc :|
4:14 a.m.
Il giorno Gio 12 Apr 2012 11:11:29 CEST, Daniel P. Berrange ha scritto:
[...]
Err, yes they are the live stats. 'memory' shows the current
memory
consumed by the VM, while 'cpuTime' shows the absolute CPU time
consumed since boot. To get % CPU time, take two readings 'n' seconds
apart and calculate the delta between them
Daniel
NOW it's clear! Thank you very much Daniel!
--
RaSca
Mia Mamma Usa Linux: Niente è impossibile da capire, se lo spieghi bene!
rasca(a)miamammausalinux.org
http://www.miamammausalinux.org
4:08 a.m.
On 12.04.2012 09:21, RaSca wrote:
Hi everybody,
I'm using the PHP API to make a web interface interact with the virtual
machines installed on some hypervisor.
Everything is fine, but I would like to find a way to get the guest's
cpu and mem usage, so that it should be possible to make some rrd
graphs. I didn't find out anything and also it seems looking around that
there is no way to obtain those data.
What is strange for me is that programs like virt-top are showing
exactly what I'm looking for. Can anyone help me to find out a way to
retrieve those statistics?
Another related question: do you think I can obtain the same data by
using this:
ps aux | egrep "[/]usr/libexec/qemu-kvm.*libvirt.*" | awk '{print
$3"/"$4}'
This takes into account memory used by hypervisor itself.
Either you need to extend libvirt-php; or you can do:
$stats = exec("virsh dommemstat $dom");
However, I lean towards libvirt-php extension.
Michal
4:13 a.m.
Il giorno Gio 12 Apr 2012 11:08:09 CEST, Michal Privoznik ha scritto:
[...]
This takes into account memory used by hypervisor itself.
Either you need to extend libvirt-php; or you can do:
$stats = exec("virsh dommemstat $dom");
However, I lean towards libvirt-php extension.
Michal
Hi Michal and thank you, libvirt-php has already got a
libvirt_domain_memory_stats function, but it returns always an array in
with just the 6th element has a value, and it is always the same value
as the total memory of the guest.
What then about the cpu? Is the CPU time useful to do statistics? How
can I interpret this value?
Thanks again,
--
RaSca
Mia Mamma Usa Linux: Niente è impossibile da capire, se lo spieghi bene!
rasca(a)miamammausalinux.org
http://www.miamammausalinux.org
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RaSca