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 enabled/disabled for HPMPI or with IB end, could you analyze the same with OPMPI too?
(e) Could you mail the log files for both.