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ComputationalRadiationPhysics / libSplash

libSplash - Simple Parallel file output Library for Accumulating Simulation data using Hdf5
GNU Lesser General Public License v3.0
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OpenMPI: Use ROMIO for IO #280

Open ax3l opened 5 years ago

ax3l commented 5 years ago

A note on using libSplash with OpenMPI:

OpenMPI's default for its IO backend is OMPIO, starting with 2.x.

Unfortunately, that backend contains severe bugs leading to data corruption and sporadic crashes as of the latest releases (e.g. 3.1.3 and 4.0.0). Please see https://github.com/open-mpi/ompi/issues/6285 for details.

As a work-around for all systems that rely on OpenMPI (and its derivatives, such as BullMPI), disable the "OMPIO" default IO backend and fallback to the existing ROMIO backend for MPI-I/O until fixed versions are available.

Available runtime switches:

export OMPI_MCA_io=^ompio
mirun ...

or

mpirun --mca io ^ompio ...

Other MPI implementations such as MPICH, and MPICH-based flavors such as IntelMPI, use ROMIO by default (they develop ROMIO) and are not affected.

ax3l commented 4 years ago

Issue continued in: https://github.com/openPMD/openPMD-api/issues/446