Intel® MPI Library Developer Reference for Linux* OS

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ID 768732
Date 3/31/2023
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Document Table of Contents
Document Table of Contents x
Intel® MPI Library Developer Reference for Linux* OS
Intel® MPI Library Developer Reference for Linux* OS x
Introduction Command Reference Environment Variable Reference Miscellaneous Notices and Disclaimers
Introduction x
Introducing Intel® MPI Library What's New Notational Conventions Related Information
Command Reference x
Compiler Commands mpirun mpiexec.hydra cpuinfo impi_info mpitune mpitune_fast
Compiler Commands x
Compilation Command Options
mpiexec.hydra x
Global Hydra Options Local Hydra Options gtool Options
mpitune x
mpitune Configuration Options
Environment Variable Reference x
Compilation Environment Variables Hydra Environment Variables I_MPI_ADJUST Family Environment Variables Tuning Environment Variables Process Pinning GPU Support Environment Variables for Fabrics Control Environment Variables for Memory Policy Control Environment Variables for Asynchronous Progress Control Environment Variables for Multi-EP Other Environment Variables
Tuning Environment Variables x
Autotuning
Autotuning x
I_MPI_TUNING_AUTO Family Environment Variables
Process Pinning x
Environment Variables for Process Pinning Interoperability with OpenMP* API
GPU Support x
GPU Pinning GPU Buffers Support
Environment Variables for Fabrics Control x
Communication Fabrics Control Shared Memory Control OFI*-capable Network Fabrics Control I_MPI_OFI_PROVIDER I_MPI_OFI_PROVIDER_DUMP I_MPI_OFI_DRECV I_MPI_OFI_LIBRARY_INTERNAL Example I_MPI_OFI_TAG_DYNAMIC
Miscellaneous x
Java* Bindings for MPI-2 Routines
Intel® MPI Library Developer Reference for Linux* OS

OFI*-capable Network Fabrics Control

I_MPI_OFI_PROVIDER

Define the name of the OFI provider to load.

Syntax

I_MPI_OFI_PROVIDER=<name>

Arguments

<name> The name of the OFI provider to load

Description

Set this environment variable to define the name of the OFI provider to load. If you do not specify this variable, the OFI library chooses the provider automatically. You can check all available providers by using the I_MPI_OFI_PROVIDER_DUMP environment variable. If you set the wrong name for an available provider, use FI_LOG_LEVEL=debug  to get a hint to set the name  correctly.

I_MPI_OFI_PROVIDER_DUMP

Control the capability of printing information about all OFI providers and their attributes from an OFI library.

Syntax

I_MPI_OFI_PROVIDER_DUMP=<arg>

Arguments

<arg> Binary indicator
enable | yes | on | 1 Print the list of all OFI providers and their attributes from an OFI library
disable | no | off | 0 No action. This is the default value

Description

Set this environment variable to control the capability of printing information about all OFI providers and their attributes from an OFI library.

I_MPI_OFI_DRECV

Control the capability of the direct receive in the OFI fabric.

Syntax

I_MPI_OFI_DRECV=<arg>

Arguments

<arg> Binary indicator
enable | yes | on | 1 Enable direct receive. This is the default value
disable | no | off | 0 Disable direct receive

Description

Use the direct receive capability to block MPI_Recv calls only. Before using the direct receive capability, ensure that you use it for single-threaded MPI applications and check if you have selected OFI as the network fabric by setting I_MPI_FABRICS=ofi.

I_MPI_OFI_LIBRARY_INTERNAL

Control the usage of libfabric* shipped with the Intel® MPI Library.

Syntax

I_MPI_OFI_LIBRARY_INTERNAL=<arg>

Arguments

<arg> Binary indicator
enable | yes | on | 1 Use libfabric from the Intel MPI Library
disable | no | off | 0 Do not use libfabric from the Intel MPI Library

Description

Set this environment variable to disable or enable usage of libfabric from the Intel MPI Library. The variable must be set before sourcing the vars.sh script.

Example

$ export I_MPI_OFI_LIBRARY_INTERNAL=1
$ source <installdir> /env/vars.sh

Setting this variable is equivalent to passing the -ofi_internal option to the vars.sh script.

For more information, refer to the Intel® MPI Library Developer Guide, section Libfabric* Support.

I_MPI_OFI_TAG_DYNAMIC

Enable dynamic tag partitioning.

Syntax

I_MPI_OFI_TAG_DYNAMIC=<arg>

Arguments

<arg> Binary indicator
enable | yes | on | 1 Enable automatic OFI tag partitioning
disable | no | off | 0 Use static OFI tag layout. This is the default value

Description

Set this environment variable to enable dynamic OFI Netmod tag partitioning based on the run configuration. You can use it to get larger MPI tag space or to improve scalability in large-scale runs.

Parent topic: Environment Variables for Fabrics Control
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