[gmx-users] GPU metadynamics

[Albert]

Hello:

  I've got two GTX690 GPU in a workstation, and I compiled gromacs-4.6.3 
with plumed and MPI support. I am trying to run some metadynamics with 
mdrun with command:

  mdrun_mpi -s md.tpr -v -g md.log -o md.trr -x md.xtc -plumed 
plumed2.dat -e md.edr

but mdrun can only use 1 GPU as indicated in the log file:



4 GPUs detected on host node3:
   #0: NVIDIA GeForce GTX 690, compute cap.: 3.0, ECC:  no, stat: compatible
   #1: NVIDIA GeForce GTX 690, compute cap.: 3.0, ECC:  no, stat: compatible
   #2: NVIDIA GeForce GTX 690, compute cap.: 3.0, ECC:  no, stat: compatible
   #3: NVIDIA GeForce GTX 690, compute cap.: 3.0, ECC:  no, stat: compatible


NOTE: potentially sub-optimal launch configuration, mdrun_mpi started 
with less
       PP MPI process per node than GPUs available.
       Each PP MPI process can use only one GPU, 1 GPUs per node will be 
used.

1 GPU auto-selected for this run: #0



I am just wondering how can we use multiple GPU for such kind of jobs?

THX
Albert