[gmx-users] Launching MPI/OpenMP hybrid run

Carsten Kutzner ckutzne at gwdg.de
Tue Mar 4 13:29:23 CET 2014

On 04 Mar 2014, at 13:08, Alexander Björling <alex.bjorling at gmail.com> wrote:

> Dear users,
> I'm trying to run simulations on a cluster of nodes, each sporting two AMD
> Opteron 8-core CPU:s. I would like to have one MPI process on each CPU,
> with OpenMP threads on the 8 cores of each. I've compiled gromacs 5.0 with
> intel MPI and OpenMP enabled.
> To get it running I'm just using two nodes, so 4 MPI processes. I've been
> using various combinations of the type:
> mpirun -np 4 -perhost 2 gmx_mpi mdrun -ntomp 8 ...,
> but I never manage to get the MPI process spread out on the two nodes.
> Rather, in the example above, 4 MPI processes with 4 OpenMP threads each
> runs on the first node, and the second node does nothing.
Did you provide a hostfile / machinefile containing the names of your
nodes you want the MPI processes to be started on?


> Any hints would be most appreciated,
> Cheers,
> Alex
> -- 
> Gromacs Users mailing list
> * Please search the archive at http://www.gromacs.org/Support/Mailing_Lists/GMX-Users_List before posting!
> * Can't post? Read http://www.gromacs.org/Support/Mailing_Lists
> * For (un)subscribe requests visit
> https://maillist.sys.kth.se/mailman/listinfo/gromacs.org_gmx-users or send a mail to gmx-users-request at gromacs.org.

More information about the gromacs.org_gmx-users mailing list