Could you specify few things -
(a) The version of PG Compilers being used both for HPMPI & OMPI. Is the compilers same or the version same?
(b) Could you share the configure command given for OMPI with PG compilers?
(c) Could you compare the threads enable/disable for both cases needed?
(d) Is ptmalloc2 being supported for HPMPI or with IB end, could you analyze the same with OPMPI too?
(e) Could you mail the log files for both.