PETSc runs slower on a shared memory machine than on a cluster

[Shi Jin]

Thank you 
I rebuilt MPICH-2 with --with-device=ch3:shm and
--with-pm=gforker
I did see a slight improvement in speed. However,
compared with the cluster runs, the shared-memory
performance is still not as good at all.
So I think the problem is indeed in the memory
subsystem as Satith said.

Shi
--- Lisandro Dalcin <dalcinl at gmail.com> wrote:
> Please read the following...
> 
>
http://www-unix.mcs.anl.gov/mpi/mpich/downloads/mpich2-doc-README.txt
> 
> I think for shared-memory you should try to
> configure MPICH2 with the following:
> 
> --with-device=ch3:shm
> 
> If not, perhaps configure will default to
> --with-device=ch3:sock and
> MPICH2 will use TCP sockets.
> 
> I hope this help you.
> 
> Regards,
> 
> -- 
> Lisandro Dalcín
> ---------------
> Centro Internacional de Métodos Computacionales en
> Ingeniería (CIMEC)
> Instituto de Desarrollo Tecnológico para la
> Industria Química (INTEC)
> Consejo Nacional de Investigaciones Científicas y
> Técnicas (CONICET)
> PTLC - Güemes 3450, (3000) Santa Fe, Argentina
> Tel/Fax: +54-(0)342-451.1594
> 
> 



 
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