mpitx

Run MPI programs over tmux

With multiple nodes:

Features:

• Interactive shell for each MPI process by spawning a tmux pane for each MPI process
• Duplicated keyboard input to all MPI processes
• Support for execution on multiple nodes connected by ethernet

Setup

First make sure that tmux and mpiexec commands are available on your system.

mpitx is implemented as just one Python3 script file. We have two install options.

1. Install via pip

pip3 install git+https://github.com/s417-lama/mpitx.git

Check your installation with:

mpitx -- bash

2. Download a script file

You can simply download a Python script file: mpitx/mpitx.py

wget https://raw.githubusercontent.com/s417-lama/mpitx/main/mpitx/mpitx.py
chmod +x mpitx.py

Make sure that mpitx.py is made executable.

Check your installation with:

./mpitx.py -- bash

Usage

mpitx [OPTIONS]... -- [COMMANDS]...

• [OPTIONS]... are passed to the installed mpiexec command as-is
• [COMMANDS]... after the delimiter -- are executed by each MPI process on each tmux pane
• The delimiter -- is required

Examples

Debug an MPI program with 4 processes:

mpitx -n 4 -- gdb ./a.out

More args for gdb:

mpitx -n 4 -- gdb --args ./a.out arg1 arg2

With some MPI implementation-specific options:

mpitx --mca mpi_show_mca_params 1 -- gdb ./a.out

Environment Variables

• MPITX_MPIEXEC: custom path to mpiexec command
• MPITX_TMUX: custom path to tmux command

When these variables are unset, the default mpiexec and tmux commands are used.

Tips on tmux

Useful tmux shortcuts (<prefix> = Ctrl-b by default):

• <prefix> + z: individually operate on each pane without duplicating keyboard input
• <prefix> + &: close all panes in a window

References

• Azrael3000/tmpi
  • mpitx was inspired by tmpi
  • The main advantage of mpitx over tmpi is the support for multiple nodes

License

Copyright (c) 2022 Shumpei Shiina

Released under the MIT License. See LICENSE.