[gmx-users] Using Gpus on multiple nodes. (Feature #1591)

[Siva Dasetty]

Dear All,

I am currently able to run simulation on a single node containing 2 gpus,
but I get the following fatal error when I try to run the simulation using
multiple gpus (2 on each node) on multiple nodes (2 for example) using OPEN
MPI.

Fatal error:

Incorrect launch configuration: mismatching number of PP MPI processes and
GPUs

per node.

mdrun was started with 4 PP MPI processes per node, but you provided only 2
GPUs.

The command I used to run the simulation is

mpirun -np 4 mdrun  -s <tpr file>  -deffnm <...>  -gpu_id 01



However It at least runs if I use the following command,


mpirun -np 4 mdrun  -s <tpr file>  -deffnm <...>  -gpu_id 0011


But after referring to the following thread, I highly doubt if I am using
all the 4 gpus available in the 2 nodes combined.


https://mailman-1.sys.kth.se/pipermail/gromacs.org_gmx-developers/2014-May/007682.html



Thank you for your help in advance,

-- 
Siva