Meeting 2021 11 11 - openpmix/openpmix GitHub Wiki

09/30/2021 PMIx call notes

Attendees

  • Ralph Castain (Nanook)
  • Michael Karo (Altair)
  • Matt Baker (ORNL)
  • Thomas Naughton (ORNL)
  • Austen Lauria (IBM)
  • Aurelien Bouteiller (UTK)

Notes

  • Issue w/ configure logic for embedding things (i.e., the "co-build" problem)

  • The 4.1.x release has some ompi specific configure code

  • The 4.2.x pmix/prrte branch has stripped down configury and will be used by packagers (master matching 4.2.0 and 2.2.1)

  • Can not bump ompi submodule pointers

  • This is only an issue when embedding and the configury pieces.

  • A few hwloc details that may impace 4.2.0/2.2.1 release schedule

  • Also need to iron out mac param/envvar namespace changes (OMPI_xxx now PRTE_xxx)

  • slurm fork in openpmix repo, an alternative approach using pmix. this will provide more support for pmix to overcome limitations. more details in future

  • mca param processing due to recent splitting between pmix/prte/ompi

    • command-line: --mca xyz

      • prrte has translation code to try and detect --mca xyz and see if xyz fits within prrte or pmix

    • mca params file -- do not have this translation, question if should just use separate file or should translated (possibly w/ deprecation warning)

    • envvar params -- do not have the translation here yet either

    • discussion about few cases

    • question about ordering of processing param files if item appears in the ompi and prte default param file, there could be an ordering question as to which should be used (i.e., order of mca param files at the same level e.g., system-ompi-param, system-prte-param, or user-ompi-param/user-prte-param)

    • discussion, may be able to use the "dry-run" kind of options that will dump the MCA params and options used when invoking the run (should have the needed hooks in opal, etc. to do much of this)

  • Question: What should ompi btl be inherited for prte's ptl? (may need to have a default and allow for override.)

  • Note - See also Geoff Paulsen's email on ompi-devel, "Subject: [EXTERNAL] [OMPI devel] OMPI -> PRRTE MCA parameter changes in Open MPI v5.0"

  • No meeting in two weeks due to Thanksgiving holiday in states, but may have a 1-off meeting in three weeks (2-dec-2021) to sync-up. If progress/need to meet next week (18-nov-2021) may meet too, but some will be attending SC'21.