HPC/Applications/lammps/Package GPU

Package GPU

• Provides multi-threaded versions of most pair styles, all dihedral styles and a few fixes in LAMMPS; for the full list:
  1. In your browser, open http://lammps.sandia.gov/doc/Section_commands.html#comm
  2. Search for the string /cuda.
• Supports one physical GPU per LAMMPS MPI process (CPU core).
• Multiple MPI processes (CPU cores) can share a single GPU, and in many cases it will be more efficient to run this way.

Usage

1. Use the lmp_mpi-gpu binary instead of the MPI-only one.
2. Use a GPU potential style. Do one of the following:
   • Append /gpu to the style name (e.g. pair_style lj/cut/gpu).
   • Use the command suffix gpu.
   • On the command line, use the -suffix gpu.
3. Detail the GPU request. Do one of the following:
   • Near the beginning of your LAMMPS control script, use the command package gpu Ngpu . Since all Carbon GPU nodes have just one GPU per node, the Ngpu argument must be 1.
   • Add -package gpu 1 to the command line options. This is perhaps preferred because you do not need to alter your input file.
4. In the job file or qsub command line, request a node having a GPU, using #PBS -l nodes=...:gpus=1 (referring to the number of GPUs per node).

Job file example

#PBS -l nodes=...:gpus=1
…
mpirun … lmp_mpi-gpu -sf gpu -pk gpu 1 -in infile