Q-Logic IB6054601-00 D manual Using MPI.mod Files, HP-MPI mpirun and executable used together

Q

C – Troubleshooting InfiniPath MPI Troubleshooting

The following two commands will both work properly:

QLogic mpirun and executable used together:

$ mpirun -m ~/host-bbb -np 4 /usr/bin/mpi_nxnlatbw

HP-MPI mpirun and executable used together:

$ /opt/hpmpi/bin/mpirun -hostlist \ "bbb-01,bbb-02,bbb-03,bbb-04" -np 4 ./hpmpi-mpi_nxnlatbw

Hints:

Use the rpm command to find out which RPM is installed in the standard installed layout. For example:

#rpm -qf /usr/bin/mpirun

mpi-frontend-2.0-964.731_fc3_psc.i386.rpm

Check all rcfiles and /opt/infinipath/etc/mpirun.defaults to make sure that the paths for binaries and libraries ($PATH and $LD_LIBRARY _PATH) are consistent.

When compiling, use descriptive names for the object files.

See section C.8.4, section C.8.5, and section C.8.6 for additional information.

C.8.8

Process Limitation with ssh

MPI jobs that use more than 8 processes per node may encounter an ssh throttling mechanism that limits the amount of concurrent per-node connections to 10. If you have this problem, you will see a message similar to this when using mpirun:

$ mpirun -m tmp -np 11 ~/mpi/mpiworld/mpiworld

ssh_exchange_identification: Connection closed by remote host

MPIRUN: Node program(s) exited during connection setup

If you encounter a message like this, you or your system administrator should increase the value of ’MaxStartups’ in your sshd configurations.

C.8.9

Using MPI.mod Files

MPI.mod (or mpi.mod) are the Fortran90/Fortran95 mpi modules files. These contain the Fortran90/Fortran95 interface to the platform-specific MPI library. The module file is invoked by ‘USE MPI’ or ‘use mpi’ in your application. If the application has an argument list that doesn’t match what mpi.mod expects, errors such as this can occur:

$ mpif90 -O3 -OPT:fast_math -c communicate.F

call mpi_recv(nrecv,1,mpi_integer,rpart(nswap),0,

IB6054601-00 D C-19