MVAPICH

MVAPICH is a standard library for performing parallel processing using a distributed-memory model. 

Availability and Restrictions

Versions

The following versions of MVAPICH are available on OSC systems:

You can use module spider mvapich/ to view available modules for a given machine. Feel free to contact OSC Help if you need other versions for your work.

Access

MPI is available to all OSC users. If you have any questions, please contact OSC Help.

Publisher/Vendor/Repository and License Type

NBCL, The Ohio State University/ Open source 

Usage

Set-up

To set up your environment for using the MPI libraries, you must load the appropriate module:

module load mvapich

You will get the default version for the compiler you have loaded.

Building With MPI

To build a program that uses MPI, you should use the compiler wrappers provided on the system. They accept the same options as the underlying compiler. The commands are shown in the following table.

For example, to build the code my_prog.c using the -O2 option, you would use:

mpicc -o my_prog -O2 my_prog.c

In rare cases you may be unable to use the wrappers. In that case you should use the environment variables set by the module.

For example, to build the code my_prog.c without using the wrappers you would use:

mpicc -c $MPI_CFLAGS my_prog.c

mpicc -o my_prog my_prog.o $MPI_LIBS

Batch Usage

Programs built with MPI can only be run in the batch environment at OSC. For information on starting MPI programs using the srun command, see Batch Processing at OSC.

Be sure to load the same compiler and mvapich modules at execution time as at build time.

Known Issues

HWloc warning: Failed with: intersection without inclusion

Handling full-node MPI warnings with MVAPICH 3.0

Further Reading

• The Message Passing Interface (MPI) Standard

See Also

• Intel MPI
• OpenMPI