Environment Variables for Multi-EP

Intel® MPI Library Developer Guide for Windows*Linux* OS

Note

This feature is supported for the release_mt and debug_mt library configurations only. To specify the configuration, run the following command:

$ source <installdir>/bin/vars.sh release_mt

I_MPI_THREAD_SPLIT

Syntax

I_MPI_THREAD_SPLIT=<value>

Arguments

<value> Binary indicator
0 | no | off | disable Disable the MPI_THREAD_SPLIT model support. This is the default value
1 | yes | on | enable Enable the MPI_THREAD_SPLIT model support

Description

Use this environment variable to control the I_MPI_THREAD_SPLIT programming model.

I_MPI_THREAD_RUNTIME

Syntax

I_MPI_THREAD_RUNTIME=<value>

Arguments

<value> Thread runtime
generic Enable runtime support (for example, pthreads, TBB). This is the default value if OpenMP* cannot be detected at runtime
openmp Enable OpenMP* runtime support. This is the default value if OpenMP is detected at runtime.

Description

Use this environment variable to control threading runtime support.

Note

I_MPI_THREAD_SPLIT model support is enabled.

I_MPI_THREAD_MAX

Syntax

I_MPI_THREAD_MAX=<int>

Arguments

<int> The maximum number of threads per rank. The default value is omp_get_max_threads() if I_MPI_THREAD_RUNTIME is set to openmp, 1 otherwise

Description

Use this environment variable to set the maximum number of threads to be used in each process concurrently.

I_MPI_THREAD_ID_KEY

Syntax

I_MPI_THREAD_ID_KEY=<string>

Arguments

<string> Define the MPI info object key. The default value is thread_id

Description

Use this environment variable to set the MPI info object key that is used to explicitly define the logical thread number thread_id.