[Beowulf] Threaded code

Art Edwards arthur.edwards at kirtland.af.mil
Tue Aug 17 13:14:54 EDT 2004


It is conceivable, but unlikely. Including blas3 in the build increases
the speed of the code by a factor of 2-3. The jobs take either days or
weeks.

Art

On Tue, Aug 17, 2004 at 01:05:13PM -0400, Joe Landman wrote:
> Art:
> 
>  Is it possible that the parallel section completes very quickly?  Or 
> that code path is not taken?
> 
> Joe
> 
> Art Edwards wrote:
> 
> >I mean that when we run the threaded code and look at top, don't see two
> >processors running. The load is always less than or equal to one. When
> >we run two separate jobs, we see a load of 2. 
> >
> >Art Edwards
> >
> >On Tue, Aug 17, 2004 at 07:45:32AM -0700, Alvin Oga wrote:
> > 
> >
> >>hi ya
> >>
> >>yup.. that is dual cpu
> >>
> >>On Tue, 17 Aug 2004, Art Edwards wrote:
> >>
> >>   
> >>
> >>>We are running SuSE 9.1 on a system with 8 GB of ram and two scsi disks.
> >>>Here is /proc/cpuinfo
> >>>processor       : 0
> >>>     
> >>>
> >>good
> >>
> >>   
> >>
> >>>processor       : 1
> >>>     
> >>>
> >>good
> >>
> >>   
> >>
> >>>Linux bladerunner 2.6.4-52-smp #1 SMP Wed Apr 7 01:58:54 UTC 2004 x86_64
> >>>x86_64 x86_64 GNU/Linux
> >>>     
> >>>
> >>good
> >>
> >>
> >>   
> >>
> >>>>Newbie question:
> >>>>
> >>>>We just purchased a dual opteron box that is running an SMP kernel. We
> >>>>have built a fortran code using g77 and a pthreaded atlas. Currently, we
> >>>>see only one processor. What really simple thing have we missed?
> >>>>       
> >>>>
> >>so what do you mean by "see only one processor" ??
> >>
> >>c ya
> >>alvin
> >>   
> >>
> >
> > 
> >
> 
> 
> -- 
> Joseph Landman, Ph.D
> Founder and CEO
> Scalable Informatics LLC,
> email: landman at scalableinformatics.com
> web  : http://www.scalableinformatics.com
> phone: +1 734 612 4615

-- 
Art Edwards
Senior Research Physicist
Air Force Research Laboratory
Electronics Foundations Branch
KAFB, New Mexico

(505) 853-6042 (v)
(505) 846-2290 (f)
_______________________________________________
Beowulf mailing list, Beowulf at beowulf.org
To change your subscription (digest mode or unsubscribe) visit http://www.beowulf.org/mailman/listinfo/beowulf



More information about the Beowulf mailing list