[Users] Memory usage

[Koen Vanoppen]

OK,
Thanks for the helpfull information. Learned something more again!

Kind regards,
Koen
On Feb 12, 2014 5:22 PM, "Doron Fediuck" <dfediuck at redhat.com> wrote:

>
>
> ----- Original Message -----
> > From: "René Koch" <rkoch at linuxland.at>
> > To: "Koen Vanoppen" <vanoppen.koen at gmail.com>
> > Cc: users at ovirt.org
> > Sent: Wednesday, February 12, 2014 4:18:37 PM
> > Subject: Re: [Users] Memory usage
> >
> > On Wed, 2014-02-12 at 15:14 +0100, Koen Vanoppen wrote:
> > > In The GUI, it says it's using 25% of the memory.
> >
> >
> > I guess it's the real value, right?
> > The same happened for the memcached vm, someone reported to me -
> > negative value in REST-API, but correct graph in oVirt webadmin GUI.
> >
> > I fear I have no idea how this can happen - so maybe someone else can
> > help you troubleshoot this issue.
> > >
> > >
> > >
> > > 2014-02-12 15:10 GMT+01:00 Koen Vanoppen <vanoppen.koen at gmail.com>:
> > >         Thanks for the quick respons, but there is no memcached
> > >         running on that VM.
> > >
> > >
> > >         Kind regards
> > >
> > >
> > >
> > >         2014-02-12 15:06 GMT+01:00 René Koch <rkoch at linuxland.at>:
> > >
> > >                 On Wed, 2014-02-12 at 14:55 +0100, Koen Vanoppen
> > >                 wrote:
> > >                 > Dear all,
> > >                 >
> > >                 >
> > >                 > When we monitor one of our machines, we noticed that
> > >                 there was one vm
> > >                 > that was constantly giving a error of memory usage.
> > >                 But when we took a
> > >                 > look at it, there is actually nothing wrong with it.
> > >                 Now we looked
> > >                 > furhter then that. We looked at the API of the
> > >                 machine and noticed
> > >                 > something very strange:
> > >                 >
> > >                 > <statistic
> > >                 >
> > >
> href="/api/vms/3b9aa245-75ff-42e8-b921-1c9ce61826bf/statistics/b7499508-c1c3-32f0-8174-c1783e57bb08"
> > >
> id="b7499508-c1c3-32f0-8174-c1783e57bb08"><name>memory.used</name><description>Memory
> > >                 used (agent)</description><values
> > >
> type="INTEGER"><value><datum>-944892806</datum></value></values><type>GAUGE</type><unit>BYTES</unit>
> > >                 >
> > >                 >
> > >                 > It's a negative...
> > >
> > >
> > >
> > >                 Do you have memcached running in this vm?
> > >
> > >                 I heard about this issue with memcached, but never
> > >                 tested memcached in
> > >                 my oVirt environment. You get the real usage value
> > >                 with
> > >                 memory.used = memory.installed + memory.used
> > >
> > >
> > >                 Regards,
> > >                 René
> > >
> > >                 >
> > >                 >
> > >                 > What could be the problem?
> > >                 >
> > >                 >
> > >                 > Kind regards,
> > >                 >
> > >                 > koen
> > >                 >
> > >
>
> Guys,
> these values are usually a result of overcommitment mechanism usage.
> For example, if KSM is effective, it will free a lot of memory pages,
> and total-free-committed becomes negative.
>
> This was reported in https://bugzilla.redhat.com/show_bug.cgi?id=977758
> and the engine is using memFree reported by vdsm, which is more accurate.
>
> The API reports the old version due to backwards compatibility.
>
> Doron
>
> P.S.
> René- thanks for helping!
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.ovirt.org/pipermail/users/attachments/20140212/06969e99/attachment-0001.html>