[Swift-user] Job bundles

[Ben Clifford]

That's what the ppn parameter specifies to PBS.

On Tue, 6 Nov 2007, Ioan Raicu wrote:

> Right, its not that PBS doesn't support it, its more of a policy thing.  On
> the TeraGrid, my experience has been that when PBS (or whatever LRM is being
> used) allocates CPUs, it always allocates at the machine level, not at the CPU
> level.  That means, if you have an 8 processor machine, and you get 1
> processor on that machine, then you get (and are charged for) the whole
> machine as you have exclusive rights to this machine for the duration of your
> reservation.  I have seen this behave differently in other environments, such
> as TeraPort, where PBS was allocating at the processor level, and not the
> machine level.  This is why I said that I think Swift would need to somehow
> handle this at the worker node scripts, and not rely necessarily on the LRM
> doing this. 
> Ioan
> 
> Ben Clifford wrote:
> > On Tue, 6 Nov 2007, Ioan Raicu wrote:
> > 
> >   
> > > 2) the LRM allows the partitioning of the SMP machine into smaller pieces;
> > > for
> > > example, with 8 processor node, if it lets you submit 8 jobs that only
> > > need 1
> > > processor, and it will launch 8 different jobs on the same node, then you
> > > are
> > > fine... the parallelism will be done automatically by the LRM, as long as
> > > you
> > > ask for only 1 process at a time; on the TG at least, I don't think this
> > > is
> > > how things work, and when you get a node, regardless of how many
> > > processors it
> > > has, you get full access to all processors, not just the ones you asked
> > > for.
> > >     
> > 
> > 
> > PBS allows the specification of multiple processes per node, like this
> > (grabbed from google)
> > 
> >   
> > > qsub -l walltime=15:00,nodes=1:ppn=1 script.pbs
> > >     
> > 
> > It looks like abe runs PBS.
> > 
> > So I think you could specify a globus profile key in the sites.xml, perhaps
> > something like this:
> > 
> >  <profile namespace="globus" key="ppn">8</profile>
> > 
> > I haven't tried this myself, but I'd be interested to hear your results.
> >   
> 
>