The MPI specification was developed by the MPI Forum, a group of software developers, computer vendors, academics, and computer-science researchers whose goal was to develop a standard for writing message-passing programs that would be efficient, flexible, and portable.
The outcome, known as the MPI Standard, was first published in 1993; its most recent version (MPI-2) was published in July 1997. Open MPI 1.2 includes all MPI 1.2-compliant and MPI 2-compliant routines.
For more information about Open MPI, see the following URL:
The MPI standards are available at the following URL:
For more information on arguments, see the orterun.1 man page.
For a complete listing of MCA parameters and their descriptions, issue the command ompi_info -h or ompi_info -param all all. This information also appears in the FAQ on the Open MPI web site at:
For more information on Open MPI error codes, see mpi.h in the include directory.
Standard error return classes for Open MPI:
MPI_SUCCESS 0 Successful return code. MPI_ERR_BUFFER 1 Invalid buffer pointer. MPI_ERR_COUNT 2 Invalid count argument. MPI_ERR_TYPE 3 Invalid datatype argument. MPI_ERR_TAG 4 Invalid tag argument. MPI_ERR_COMM 5 Invalid communicator. MPI_ERR_RANK 6 Invalid rank. MPI_ERR_REQUEST 7 Invalid MPI_Request handle. MPI_ERR_ROOT 7 Invalid root. MPI_ERR_GROUP 8 Null group passed to function. MPI_ERR_OP 9 Invalid operation. MPI_ERR_TOPOLOGY 10 Invalid topology. MPI_ERR_DIMS 11 Illegal dimension argument. MPI_ERR_ARG 12 Invalid argument. MPI_ERR_UNKNOWN 13 Unknown error. MPI_ERR_TRUNCATE 14 Message truncated on receive. MPI_ERR_OTHER 15 Other error; use Error_string. MPI_ERR_INTERN 16 Internal error code. MPI_ERR_IN_STATUS 17 Look in status for error value. MPI_ERR_PENDING 18 Pending request. MPI_ERR_ACCESS 19 Permission denied. MPI_ERR_AMODE 20 Unsupported amode passed to open. MPI_ERR_ASSERT 21 Invalid assert. MPI_ERR_BAD_FILE 22 Invalid file name (for example, path name too long). MPI_ERR_BASE 23 Invalid base. MPI_ERR_CONVERSION 24 An error occurred in a user-supplied data-conversion function. MPI_ERR_DISP 25 Invalid displacement. MPI_ERR_DUP_DATAREP 26 Conversion functions could not be registered because a data representation identifier that was already defined was passed to MPI_REGISTER_DATAREP. MPI_ERR_FILE_EXISTS 27 File exists. MPI_ERR_FILE_IN_USE 28 File operation could not be completed, as the file is currently open by some process. MPI_ERR_FILE 29 MPI_ERR_INFO_KEY 30 Illegal info key. MPI_ERR_INFO_NOKEY 31 No such key. MPI_ERR_INFO_VALUE 32 Illegal info value. MPI_ERR_INFO 33 Invalid info object. MPI_ERR_IO 34 I/O error. MPI_ERR_KEYVAL 35 Illegal key value. MPI_ERR_LOCKTYPE 36 Invalid locktype. MPI_ERR_NAME 37 Name not found. MPI_ERR_NO_MEM 38 Memory exhausted. MPI_ERR_NOT_SAME 39 MPI_ERR_NO_SPACE 40 Not enough space. MPI_ERR_NO_SUCH_FILE 41 File (or directory) does not exist. MPI_ERR_PORT 42 Invalid port. MPI_ERR_QUOTA 43 Quota exceeded. MPI_ERR_READ_ONLY 44 Read-only file system. MPI_ERR_RMA_CONFLICT 45 Conflicting accesses to window. MPI_ERR_RMA_SYNC 46 Erroneous RMA synchronization. MPI_ERR_SERVICE 47 Invalid publish/unpublish. MPI_ERR_SIZE 48 Invalid size. MPI_ERR_SPAWN 49 Error spawning. MPI_ERR_UNSUPPORTED_DATAREP 50 Unsupported datarep passed to MPI_File_set_view. MPI_ERR_UNSUPPORTED_OPERATION 51 Unsupported operation, such as seeking on a file that supports only sequential access. MPI_ERR_WIN 52 Invalid window. MPI_ERR_LASTCODE 53 Last error code. MPI_ERR_SYSRESOURCE -2 Out of resources