On 13 Nov 2018, at 10:11, Chris Eldred <chris.eldred@gmail.com> wrote:
Hey Lawrence,
I followed the advice at https://github.com/firedrakeproject/firedrake/issues/1325 and used sudo update-alternatives --config mpi sudo update-alternatives --config mpirun to select mpich instead of openmpi.
Now mpicc -show gives gcc -Wl,-Bsymbolic-functions -Wl,-z,relro -I/usr/include/mpich -L/usr/lib/x86_64-linux-gnu -lmpich which seems right.
But when I run in parallel using mpirun -n X python3 foo.py it simply runs (as noted in the issue referenced above) X copies of foo.py in serial.
What is the correct way to get Firedrake working in parallel on Ubuntu 18.04?
Also, I would suggest writing up some instructions and putting them on the website (I am happy to do this) since the "obvious" approach of mpirun -n X python3 foo.py has a nasty and non-obvious failure mode.
You also need to rebuild firedrake to link against MPICH. Run with firedrake-install --no-package-manager ... Cheers, Lawrence