YogiMPI Overview

• Prerequisites

  • Intel or GNU (4.8+) C, C++, and Fortran compiler
  • MPI distribution with compiler wrappers (e.g. mpicc, mpicxx, mpif90)
  • MPI distribution must support at least the MPI v2.1 API.

• Installation

  • Load your compilers and MPI wrappers into the path and runtime library path.
  • Choose an MPI API version to support. Current options are 2.1, 2.2, and 3. Set the YVERSION variable to any of these values. The default is 3.
  • Set the environment variable YCC, YCXX, and YF90 to point to your serial compilers.
  • As an alternative to the above compiler variables, you may also specify YFAMILY=gnu or YFAMILY=intel, which will set the variables to the default values of gcc, g++, and gfortran for GNU and icc, icpc, and ifort for Intel. This also sets some compiler flags.
  • If you are using the GNU Fortran compiler without the YFAMILY variable, you will need to add -ffree-line-length-none to FFLAGS in Make.flags for proper compilation.
  • Set the environment variable YMPICXX to point to your MPI's C++ compiler wrapper.
  • YogiMPI has optional debugging output enabled by setting the YDEBUG environment variable to 1. This will create a yogimpi.log.<global_rank> file for each MPI rank, and it will list functions entered and exited by the rank. Use only when required. This can be useful when you create a "release" and "debug" version of Yogi as they can be swapped out for each other as needed.
  • Once set, run ./configure -i /path/to/install
  • To build, type "make," and then "make install" to copy files to the installation directory.
  • Note that some MPI deprecation warnings may be given. These may be ignored.

• Testing

  • A small set of C and Fortran tests ship with YogiMPI to ensure that basic functionality works as expected. This is not a comprehensive test suite but a small subset of commonly used MPI routines.
  • After "make" and "make install" (the installation must run), change into the test subdirectory.
  • "make runtest" will build and execute all tests. If successful, a message will be printed.

• Modules and Source Files

  • As part of the installation, module files and a bash script are provided in /path/to/install/etc. These can be used to add YogiMPI to the PATH and [DY]LD_LIBRARY_PATH.

• Version Numbering

  • An release candidate increase (1.1.1rc1 -> 1.1.1rc2) is a minor bug fix or similar change in preparation for a new release.
  • An example of a patch release (1.1.Z) would be adding support for an MPI function without changing existing behavior.
  • An ABI change requires incrementing the minor release number (1.Y.0).
  • A major release increment (X.0.0) would only be for a major interface change.