Helpful guidelines

What does mpiexec do?

What does mpiexec do?

The mpiexec command is the typical way to start parallel or serial jobs. It hides the differences of starting jobs of various implementations of the Message Passing Interface, version 2, from the user.

What is the difference between Mpirun and Mpiexec?

mpiexec is defined in the MPI standard (well, the recent versions at least) and I refer you to those (your favourite search engine will find them for you) for details. mpirun is a command implemented by many MPI implementations.

What is Mpiexec Hydra?

Since Hydra does things differently than MPD, the Hydra-based mpiexec takes different command-line arguments than the MPD-based one and to make it possible for users to explicitly select the Hydra-based one, it is made available as mpiexec. hydra . The old one is called mpiexec.

How do I run an MPI program in Python?

Python programs that use MPI commands must be run using an MPI interpreter, which is provided with the command mpirun . On some systems this command is instead called mpiexec and mpi4py seems to include both. Here the -n 4 tells MPI to use four processes, which is the number of cores I have on my laptop.

What is the difference between OpenMPI and Mpich?

MPICH has built-in debugger, while Open-MPI does not last time I checked. In production, Open-MPI most likely will be faster. But then you may want to research other alternatives, such as Intel MPI.

What is OpenMPI used for?

MPI is a standard library for performing parallel processing using a distributed memory model. The Ruby, Owens, and Pitzer clusters at OSC can use the OpenMPI implementation of the Message Passing Interface (MPI).

What is Hydra MPI?

Hydra is a process management system for starting parallel jobs. Hydra is designed to natively work with multiple daemons such as ssh, rsh, pbs, slurm and sge.

What is MPI for Python?

MPI for Python provides Python bindings for the Message Passing Interface (MPI) standard, allowing Python applications to exploit multiple processors on workstations, clusters and supercomputers. This package builds on the MPI specification and provides an object oriented interface resembling the MPI-2 C++ bindings.