NAME

       ompi_info - Display information about the Open MPI installation

SYNOPSIS

       ompi_info [options]

DESCRIPTION

       ompi_info  provides  detailed information about the Open MPI installation.  It can be useful for at least
       three common scenarios:

       1. Checking local configuration and seeing how Open MPI was installed.

       2.  Submitting  bug  reports  /  help  requests  to  the  Open  MPI   community   (see   http://www.open-
       mpi.org/community/help/)

       3. Seeing a list of installed Open MPI plugins and querying what MCA parameters they support.

       NOTE: ompi_info defaults to only showing a few MCA parameters by default (i.e., level 1 parameters).  Use
       the --level option to enable showing more options (see the LEVELS section for more information).

OPTIONS

       ompi_info accepts the following options:

       -a|--all
               Show all configuration options and MCA parameters.  Also changes the default MCA parameter  level
               to 9, unless --level is also specified.

       --arch  Show architecture on which Open MPI was compiled.

       -c|--config
               Show configuration options

       -gmca|--gmca <param> <value>
               Pass global MCA parameters that are applicable to all contexts.

       -h|--help
               Shows help / usage message.

       --hostname
               Show the hostname on which Open MPI was configured and built.

       --internal
               Show internal MCA parameters (not meant to be modified by users).

       --level <level>
               Show  only  variables  with  at most this level (1-9). The default is 1 unless --all is specified
               without --level, in which case the default is 9. See the LEVELS section for more information.

       -mca|--mca <param> <value>
               Pass context-specific MCA parameters; they are considered global if --gmca is not used  and  only
               one context is specified.

       --param <type> <component>
               Show  MCA  parameters.   The  first parameter is the type of the component to display; the second
               parameter is the specific component to display  (or  the  keyword  "all",  meaning  "display  all
               components of this type").

       -t|--type
               Show  MCA  parameters  of  the type specified in the parameter. Accepts the following parameters:
               unsigned_int, unsigned_long, unsigned_long_long, size_t, string, version_string, bool, double. By
               default level is 1 unless it is specified with --level.

       --parsable
               When  used  in  conjunction  with other parameters, the output is displayed in a machine-parsable
               format --parseable Synonym for --parsable

       --path <type>
               Show paths that Open MPI was configured with.  Accepts the following parameters: prefix,  bindir,
               libdir, incdir, pkglibdir, sysconfdir.

       --pretty
               When  used  in conjunction with other parameters, the output is displayed in 'prettyprint' format
               (default)

       --selected-only
               Show only variables from selected components.

       -V|--version
               Show version of Open MPI.

LEVELS

       Open MPI has many, many run-time tunable  parameters  (called  "MCA  parameters"),  and  usually  only  a
       handfull of them are useful to a given user.

       As  such,  Open  MPI  has  divided  these parameters up into nine distinct levels, broken down into three
       categories, each with three sub-categories.

       Note that since each MCA parameter is accessible through the MPI_T control variable  API  (introduced  in
       MPI-3.0), these levels exactly correspond to the nine MPI_T cvar levels.

       The three categories are:

       End user
           Generally,  these  are  parameters that are required for correctness, meaning that a user may need to
           set these just to get their MPI application to run  correctly.  For  example,  BTL  "if_include"  and
           "if_exclude" parameters fit into this category.

       Application tuner
           Generally,  these  are  parameters  that  can be used to tweak MPI application performance. This even
           includes parameters that control resource exhaustion levels (e.g., number of free list entries,  size
           of  buffers,  etc.),  and  could  be considered "correctness" parameters if they're set too low. But,
           really -- they're tuning parameters.

       Open MPI developer
           Parameters in this category either don't fit in the other  two,  or  are  specifically  intended  for
           debugging / development of Open MPI itself.

       And within each category, there are three sub-categories:

       Basic
           This  sub-category  is  for  parameters that everyone in this category will want to see -- even less-
           advanced end users, application tuners, and new OMPI developers.

       Detailed
           This sub-category is for parameters that are generally useful,  but  users  probably  won't  need  to
           change them often.

       All This sub-category is for all other parameters. Such parameters are likely fairly esoteric.

       Combining the categories and sub-categories, here's how Open MPI defines all nine levels:

       1   Basic information of interest to end users.

       2   Detailed information of interest to end users.

       3   All remaining information of interest to end users.

       4   Basic information required for application tuners.

       5   Detailed information required for application tuners.

       6   All remaining information required for application tuners.

       7   Basic information for Open MPI implementors.

       8   Detailed information for Open MPI implementors.

       9   All remaining information for Open MPI implementors.

       By  default,  ompi_info  only  shows level 1 MCA parameters.  To see more MCA parameters, use the --level
       command line option.

EXAMPLES

       ompi_info
           Show the default output of options  and  listing  of  installed  components  in  a  human-readable  /
           prettyprint format.

       ompi_info --parsable
           Show the default output of options and listing of installed components in a machine-parsable format.

       ompi_info --param btl tcp
           Show the level 1 MCA parameters of the "tcp" BTL component in a human-readable / prettyprint format.

       ompi_info --param btl tcp --level 6
           Show  the  level  1  through  level 6 MCA parameters of the "tcp" BTL component in a human-readable /
           prettyprint format.

       ompi_info --param btl tcp --parsable
           Show the level 1 MCA parameters of the "tcp" BTL component in a machine-parsable format.

       ompi_info --type string --pretty-print --level 3
           Show the level 3 MCA parameters of string type in a human-readable / prettyprint format.

       ompi_info --path bindir
           Show the "bindir" that Open MPI was configured with.

       ompi_info --version
           Show the version of Open MPI version numbers in a prettyprint format.

       ompi_info --all
           Show all information about the Open MPI installation, including all components that can be found, all
           the  MCA  parameters  that  they  support  (i.e.,  levels  1 through 9), versions of Open MPI and the
           components, etc.

AUTHORS

       The Open MPI maintainers -- see http://www.openmpi.org/ or the file AUTHORS.

       This manual page was originally contributed by Dirk Eddelbuettel  <edd@debian.org>,  one  of  the  Debian
       GNU/Linux maintainers for Open MPI, and may be used by others.