These are chat archives for Fortran-FOSS-Programmers/General-Discussion

23rd
Jul 2017
Stefano Zaghi
@szaghi
Jul 23 2017 05:30
Dear Rand
Stefano Zaghi
@szaghi
Jul 23 2017 05:36
Welcome here. Others will give you more insight, but from my experience your living dangerously ... This sounds a very cutting-edge MPI application. In my MPI code I usually send/receive base types, I am not so confident with current implementations. Recently I switched to CAF and with coarrays it seems more safe and natural communicate OO data. Anyhow, please share your test, I'll read it with interest. My best regards.
Rand Huso
@rchuso
Jul 23 2017 05:50
Hello Stefano. "living dangerously" - I like that. With my C work processing seismic survey data (sizes up to PB, and running on the largest privately owned supercomputers in the world - like Total.com), I'm currently the fastest in the industry (if I understand what our customers are saying - my applications are 3 to 5 times faster than those of CGG and others - see the GLOBE Claritas web site for some details - part of GNS Science). I'm able to do this because of how I can abstract some of the complexity of MPI for the applications I wrote (like 3D Kirchhoff time migration - seismic tomography), and I'm trying to do the same thing with Fortran. I just want to be able to send and receive objects that have a base class. What really surprises me is the different behaviour I'm seeing with MPICH and OpenMPI using the gfortran 7.1.0 vs earlier versions. I'm in the process of changing my test routine to help me track down the progress, and will include it here when ready. Thanks.
Rand Huso
@rchuso
Jul 23 2017 07:07

I got it working.

Well, it turns out the code is too large to enter here. It's at 144 lines, and successfully runs on OpenMPI 2.1 with gfortran 7.1. Is there a way to include it here for others to see?