HP-MPI User's Guide (11th Edition)

Understanding HP-MPI
MPI options
Chapter 3160
% setenv MPI_SRUNOPTION --label
% bsub -I -n4 -ext "SLURM[nodes=4]" \
$MPI_ROOT/bin/mpirun -stdio=bnone -f appfile -- pingpong
Job <369848> is submitted to default queue <normal>.
<<Waiting for dispatch ...>>
<<Starting on lsfhost.localdomain>>
/opt/hpmpi/bin/mpirun
unset
MPI_USESRUN;/opt/hpmpi/bin/mpirun
-srun ./pallas.x -npmin 4 pingpong
MPI_PRUNOPTIONS Allows prun specific options to be added
automatically to the mpirun command line. For example:
% export MPI_PRUNOPTIONS="-m cyclic -x host0"
% mpirun -prot -prun -n2 ./a.out
is equivalent to:
% mpirun -prot -prun -m cyclic -x host0 -n2 ./a.out
TCP environment variables
MPI_TCP_CORECVLIMIT The integer value indicates the number of
simultaneous messages larger than 16KB that may be transmitted to a
single rank at once via TCP/IP. Setting this variable to a larger value can
allow HP-MPI to utilize more parallelism during its low-level message
transfers, but can greatly reduce performance by causing switch
congestion. Setting MPI_TCP_CORECVLIMIT to zero will not limit the
number of simultaneous messages a rank may receive at once. The
default value is 0.
MPI_SOCKBUFSIZE Specifies, in bytes, the amount of system buffer space
to allocate for sockets when using the TCP/IP protocol for
communication. Setting MPI_SOCKBUFSIZE results in calls to setsockopt
(..., SOL_SOCKET, SO_SNDBUF, ...) and setsockopt (..., SOL_SOCKET,
SO_RCVBUF, ...). If unspecified, the system default (which on many
systems is 87380 bytes) is used.