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Re: [Condor-users] Virtual Machine universe: hands-on examples?

> -----Original Message-----
> From: condor-users-bounces@xxxxxxxxxxx [mailto:condor-users-
> bounces@xxxxxxxxxxx] On Behalf Of Rob
> Sent: 22 October 2012 08:51
> To: Ian Cottam; condor-users
> Subject: Re: [Condor-users] Virtual Machine universe: hands-on
> examples?
> ----- Original Message -----
> From: Ian Cottam <Ian.Cottam@xxxxxxxxxxxxxxxx>
> To: Rob <spamrefuse@xxxxxxxxx>; Condor-Users Mail List <condor-
> users@xxxxxxxxxxx>
> >
> > Rob,
> > I've used POVB <http://sourceforge.net/apps/trac/poolsofvirtualb/>
> > successfully, as no doubt have many others.
> > the only problem I have is when Windows PCs 'go away' due to PowerMAN
> > power saving features.
> > Condor 7.8 has changed a little how this is handled, so I may try it
> >again
> > when I have time.
> > -Ian
> >
> Thanks for sharing your experiences. I'm aware of this solution and
> I've seen a PPT on this topic somewhere on the Internet.
> The downside of this approach is that the virtual machine in VirtualBox
> is always running, even when the owner is using the PC, right?
> That is not an acceptable solution for the library IT of the university
> here; Condor is only allowed on the PCs, for as long as there is almost
> zero impact on the regular usage of the PCs.
> The original idea of the VM universe is (correct me if I'm wrong on
> this), that Condor only starts the virtual environment (e.g.
> VirtualBox) when the pool PC is idle, then feeds it with the
> virtual machine given in the submit file, and the virtual environment
> is only there as long as Condor is allowed to keep the PC busy.....
> This functionality of Condor VM seems to have disappeared when
> moving away from VMWare. If not "disappeared" as a feature, then at
> least necessary and helpful documentation has disappeared :(.
> Regards,
> Rob.

Just put in my 2c in here...

I spent quite a long time trying to use CoLinux under Condor and it seemed to
work a treat (others have gone down this path). The big advantage was that
the VM could be started from the ordinary non-privileged Condor execute account
(condor-reuse-slot something ???) and so you could start the VM as an
ordinary Condor job - it didn't need to be running all the time as a service.

Unfortunately we moved to 64-bit Windows 7 and the last time I looked, CoLinux
does not support this ( I live in hope).

I tried the same thing with VirtualBox but it would not start as a non-privileged
user - seemed to be trying to write to the registry which is a no no. It would
however start as SYSTEM via a condor_startd cron which may be something to explore.
I got in a total confused mess with VMWare Player but from what I can see this doesn't
seem to want to start as a non-privileged user either.

My worry with having the VM run all the time is that (I assume) you need
to allocate memory to it upfront. No doubt it will get swapped out if a logged in user
comes along but in the past we've had problems with large memory Condor jobs
running at the same time as a local user running a "meaty" application such
as Matlab, ABAQUS, AutoCAD etc. My feeling is that it's best to avoid having the
VM run while users are logged in (and this is particularly the case with our library



Dr Ian C. Smith,
Advanced Research Computing,
University of Liverpool, UK.