[gmx-users] documentation error?

[gromacs query]

Hi All,

Though am naive, and much appreciate the efforts required to put things
altogether but I think I found few things confusing or wrong by mistake or
repeated here:

http://manual.gromacs.org/documentation/2016/user-guide/mdrun-performance.html

The replaced corrections are in [CAPITAL] (please correct me!); specially
for ntomp is it number of threads per rank or core?

1) Mistake?

gmx mdrun -ntmpi 2 -ntomp 4

Starts mdrun using eight total threads, with four [TWO] thread-MPI ranks
and two [FOUR] OpenMP threads per core[RANK?]. You should only use these
options when seeking optimal performance, and must take care that the ranks
you create can have all of their OpenMP threads run on the same socket. The
number of ranks must be a multiple of the number of sockets[CORES?], and
the number of cores per node [OR TO BE USED ON SHARED NODE] must be a
multiple of the number of threads per rank.

2) Repeated: Explanations are repeated.

mpirun -np 20 gmx_mpi mdrun -ntomp 4 -gpu_id 0

Starts gmx mdrun
<http://manual.gromacs.org/documentation/2016/onlinehelp/gmx-mdrun.html#mdrun-mpi>
with 20 ranks, and assigns the CPU cores evenly across ranks each to one
OpenMP thread. This setup is likely to be suitable when there are ten
nodes, each with one GPU, and each node has two sockets.

mpirun -np 20 gmx_mpi mdrun -gpu_id 00

Starts gmx mdrun
<http://manual.gromacs.org/documentation/2016/onlinehelp/gmx-mdrun.html#mdrun-mpi>
with 20 ranks, and assigns the CPU cores evenly across ranks each to one
OpenMP thread. This setup is likely to be suitable when there are ten
nodes, each with one GPU, and each node has two sockets.