Open MPI logo

Open MPI User's Mailing List Archives

  |   Home   |   Support   |   FAQ   |   all Open MPI User's mailing list

Subject: Re: [OMPI users] Performance: MPICH2 vs OpenMPI
From: Sangamesh B (forum.san_at_[hidden])
Date: 2008-10-09 08:06:19


On Thu, Oct 9, 2008 at 5:40 AM, Jeff Squyres <jsquyres_at_[hidden]> wrote:

> On Oct 8, 2008, at 5:25 PM, Aurélien Bouteiller wrote:
>
> Make sure you don't use a "debug" build of Open MPI. If you use trunk, the
>> build system detects it and turns on debug by default. It really kills
>> performance. --disable-debug will remove all those nasty printfs from the
>> critical path.
>>
>
> You can easily tell if you have a debug build of OMPI with the ompi_info
> command:
>
> shell$ ompi_info | grep debug
> Internal debug support: no
> Memory debugging support: no
> shell$
>
Yes. It is "no"
$ /opt/ompi127/bin/ompi_info -all | grep debug
  Internal debug support: no
Memory debugging support: no

I've tested GROMACS for a single process (mpirun -np 1):
Here are the results:

OpenMPI : 120m 6s

MPICH2 : 67m 44s

I'm trying to bulid the codes with PGI, but facing problem with compilation
of GROMACS.

>
> You want to see "no" for both of those.
>
> --
> Jeff Squyres
> Cisco Systems
>
>
>
> _______________________________________________
> users mailing list
> users_at_[hidden]
> http://www.open-mpi.org/mailman/listinfo.cgi/users
>