Bug#954272: slurmd: SLURM not working with OpenMPI
On 20/07/2020 14:52, Lars Veldscholte wrote:
Which code is trying to load libpmix.so ? The compiled code should be
loading libpmix.so.2 directly; the libpmix.so should only be needed
I believe I have found a solution.
I must confess that I still don't fully understand the difference
between the various PMI APIs, and which ones are supported by OpenMPI,
but I found that the recommended way is to use PMIx.
However, PMIx was not working on my system even though libpmix2 is
# srun --mpi pmix ./a.out
srun: error: (null)  /mpi_pmix.c:133 [init] mpi/pmix: ERROR:
pmi/pmix: can not load PMIx library
srun: error: Couldn't load specified plugin name for mpi/pmix: Plugin
init() callback failed
srun: error: cannot create mpi context for mpi/pmix
srun: error: invalid MPI type 'pmix', --mpi=list for acceptable types
Running `strace srun --mpi=pmix ./a.out` revealed that SLURM is
looking for the pmix library at
`/usr/lib/x86_64-linux-gnu/pmix/lib/libpmix.so`, which does not exist,
only `libpmix.so.2` exists.
Perhaps the problem is that libpmix-dev is not installed at compile
time. I can add it as a Dependency of libopenmpi-dev.
Installing the package `libpmix-dev` installs this library (it
symlinks it to the same file `libpmix.so.2` is symlinked to).
Now, `srun --mpi=pmix ./a.out` is working!
I'm not 100% sure, but I think that the package `libpmix2` should also
install the file `libpmix.so`. The dev package shouldn't be required
for that, right?
Alastair McKinstry, <email@example.com>, <firstname.lastname@example.org>, https://diaspora.sceal.ie/u/amckinstry
Misentropy: doubting that the Universe is becoming more disordered.