Get Started Guide

  • 2021.1
  • 12/04/2020
  • Public Content

The Intel® MPI Library lets you create, maintain, and test advanced applications that performance advantages on high-performance computing (HPC) clusters based on Intel® processors.
The Intel MPI Library is available as a standalone product and as part of the Intel® oneAPI HPC Toolkit. The Intel MPI Library is a multi-fabric message passing library that implements the Message Passing Interface, version 3.1 (MPI-3.1) specification. Use the library to develop applications that can run on multiple cluster interconnects.
The Intel MPI Library has the following features:
  • Low overhead enables analysis of large amounts of data
  • MPI tuning utility for accelerating your applications
  • Interconnect independence and flexible runtime fabric selection
Product Contents
The product comprises the following main components:
  • Compilation tools, including compiler drivers such as
    mpiicc
    and
    mpifort
  • Include files and modules
  • Dynamic (
    .dll
    ) libraries, debug libraries, interface libraries, and program database (
    .pdb
    ) files
  • Process Manager and tools to run programs
  • Test code
  • Documentation provided as a separate package or available from the Intel Developer Zone
Besides the components above, Intel MPI Library also includes Intel® MPI Benchmarks, which enable you to measure MPI operations on various cluster architectures and MPI implementations. For details, see the
Intel MPI Benchmarks User Guide
. Source code is available in the GitHub repository.
Key Features
Intel MPI Library has the following major features:
  • MPI-1, MPI-2.2, and MPI-3.1 specification conformance
  • Interconnect independence
  • C, C++, Fortran* 77, and Fortran 90 language bindings
Prerequisites
Before you start using the Intel MPI Library, make sure to complete the following steps:
  1. Run the
    setvars.bat
    file to set the environment variables for the Intel MPI Library. The file is located in the installation directory (by default,
    C:\Program Files (x86)\Intel\oneAPI
    ).
  2. Install and run the Hydra services on the compute nodes. In the command prompt, enter:
    > hydra_service -install
    > hydra_service -start
  3. Register your credentials:
> mpiexec -register
For detailed system requirements, see the “System Requirements” section in
Release Notes
.
Building and Running MPI Programs
Compiling an MPI Program
1. Make sure you have the desired compiler installed and configured properly. For example, for the Intel® C++ Compiler, run:
> icl
If the command is not recognized, add the compiler to your
PATH
. For the Intel® compilers, you can run the
vars.bat
script from the corresponding directory.
2. Compile your program using the appropriate compiler driver. For example, for a test C program:
> mpiicc -o test.exe <install-dir>\test\test.c
Running an MPI Program
Execute the program using the
mpiexec
command. For example, for the test program:
> mpiexec -n <# of processes> test.exe
To specify the hosts to run the program on, use the
-hosts
option:
> mpiexec -n <# of processes> -ppn <# of processes per node> -hosts <host1>,<host2>,...,<hostN> test.exe
Troubleshooting
If you encounter problems when using Intel MPI Librargo through the following general procedures to troubleshoot them:
  • Check system requirements and known issues in the
    Release Notes
  • Check hosts accessibility. Try to run a simple non-MPI application (for example,
    hostname
    utility) on the problem hosts with
    mpiexec
    . This check helps you reveal the environmental or connectivity problem (for example, unreachable hosts).
  • Run the MPI application with debug information enabled. To enable the debug information, set the environment variable
    I_MPI_DEBUG=6
    . You can also set a different debug level to get more detailed information. This action helps to find out the problem component.
  • See more details in the “Troubleshooting” section of the
    Developer Guide
    .
More Resources

Product and Performance Information

1

Performance varies by use, configuration and other factors. Learn more at www.Intel.com/PerformanceIndex.