Well, we aren't really that picky :-) While I agree with Gilles that we are unlikely to be able to help you resolve the problem, we can give you a couple of ideas on how to chase it down
First, be sure to build OMPI with "--enable-debug" and then try adding "--mca oob_base_verbose 100" to you mpirun cmd line. That will dump a bunch of diagnostics from the daemon-to-daemon TCP code. Second, you can look at that code and see if you can spot something that might be MTU sensitive - the code is in the orte/mca/oob/tcp directory. HTH Ralph > On Aug 9, 2020, at 10:37 PM, John Duffy via users <users@lists.open-mpi.org> > wrote: > > Thanks Gilles > > I realise this is “off topic”. I was hoping the Open-MPI ORTE/HNP message > might give me a clue where to look for my driver problem. > > Regarding P/Q ratios, indeed P=2 & Q=16 does indeed give me better > performance. > > Kind regards
