[SAGA-RG] quick poll: SPMD attributes

[Andre Merzky]

Quoting [Andre Luckow] (Dec 12 2009):
> > Agree, they absolutely should be optional, and default to
> > 
> >  ProcessesPerMachine = unspecified
> >  ProcessesPerSockets = unspecified
> >  ProcessesPerCore    = 1
> > 
> > And right, you can't enforce number of cpus/cores, but you can set
> > upper bounds, to make either sure you are not getting on a core
> > where xxx processes are already running, or, on the other end, allow
> > the DRM to use a core for multiple process instances.
> > 
> > Makes sense?
> It does make sense. But now the next question is: What is the semantics of those attributes?
> - exactly
> - upper bound
> - lower bound
> 
> or do you want to specify a range (which complicates things even more).

IMHO they should be upper bound.  Less processors per XYZ should
give better performance, so it should be ok for the user?

I could live with exact, too - but lower bound does not make sense I
think - I don't want to end up wioth 1000 procs per core just
because its allowed by the default job description ;-)

Cheers, Andre.


-- 
Nothing is ever easy.