[gmx-users] GPU+CPU

[Parker de Waal]

Hello Everyone,

I recently started to explore GROMACS (switching over from AMBER) and need some help understanding how to launch GPU+CPU simulations.

GROMACS 5.0.6 was compiled with the following cmake arguments:
cmake .. -DGMX_BUILD_OWN_FFTW=ON -DCUDA_TOOLKIT_ROOT_DIR=/cm/shared/apps/cuda70/toolkit/7.0.28 -DGMX_MPI=ON -DCMAKE_INSTALL_PREFIX=/home/parker.dewaal/applications/gromacs-5.0.6 -DGMX_GPU=ON

Now I would like to run a simulation on a box with 28 CPU cores and 2 titan K80s (4 GPU threads), what would be the difference between running the following:

Mdrun

Mdrun –ntmpi 4 –ntomp 7

Mpirun –np 4 mdrun_mpi

Cheers,
Parker