On Oct 20, 2014, at 12:43 PM, Jeff Hammond <[email protected]> wrote: Is this because MPICH can't spawn processes except through PMI/Hydra/whatever and you - justifiably - do not want to implement a special case workaround using execvp() directly?

The new process needs a way to query for business cards and such, for which mpiexec is needed. So the current design of singleton init is to spawn mpiexec and connect to it. That’s a mess and is not clearly specified by the PMI spec. My suggestion was to execvp the executable “mpiexec” with the right arguments to relaunch the application again, but there are some problems with that: http://trac.mpich.org/projects/mpich/ticket/1074 — Pavan -- Pavan Balaji ✉️ http://www.mcs.anl.gov/~balaji