Intel® MPI Library Developer Reference for Windows* OS

ID 768734
Date 3/22/2024

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Provides information on available Intel® MPI Library environment variables.


impi_info <options>


<options> List of options.
-a | -all Show all IMPI variables.
-h | -help Show a help message.
-v | -variable Show all available variables or description of the specified variable.
-c | -category Show all available categories or variables of the specified category.
-e | -expert Show all expert variables.


The impi_info utility provides information on environment variables available in the Intel MPI Library. For each variable, it prints out the name, the default value, and the value data type. By default, a reduced list of variables is displayed. Use the  -all option to display all available variables with their descriptions.

The example of the impi_info output:

> impi_info
| NAME                                   | DEFAULT VALUE | DATA TYPE   |
| I_MPI_THREAD_SPLIT                     | 0             | MPI_INT     |
| I_MPI_THREAD_RUNTIME                   | none          | MPI_CHAR    |
| I_MPI_THREAD_MAX                       | -1            | MPI_INT     |
| I_MPI_THREAD_ID_KEY                    | thread_id     | MPI_CHAR    |