Hi Folks, Let’s meet on 1/29 to continue discussions related to sessions and FT. I think what will help is to consider several use cases and implications. Here are some I have * App using sessions to init/finalize and create at least one initial communicator with MPI_Comm_create_from_group, but also wants to use methods available in slice1 of ULFM proposal to shrink/repair communicators. Are there any problems? * App using sessions to init/finalize and create at least one initial communicator with MPI_Comm_create_from_group, and wants to use methods available in slice 1 of ULFM proposal to create new group from a pset and create a new communicator * App using sessions to init/finalize, etc. and when a fail-stop error is detected destroy the session, create a new session query for process sets, etc. and start all over. We should also consider the behavior of MPI_Comm_create_from_group if a process failure occurs while creating a new communicator. The ULFM slice 1 discusses behavior of MPI_COMM_DUP and process failure. We’d probably want similar behavior for MPI_Comm_create_from_group. For those with access, the ULFM slice 1 PR is at https://github.com/mpi-forum/mpi-standard/pull/947 Thanks, Howard ------- [signature_61897647] Howard Pritchard Research Scientist HPC-ENV Los Alamos National Laboratory [email protected]<mailto:[email protected]> [signature_1672648044]<https://www.instagram.com/losalamosnatlab/>[signature_2067890307]<https://twitter.com/LosAlamosNatLab>[signature_1942525183]<https://www.linkedin.com/company/los-alamos-national-laboratory/>[signature_882949974]<https://www.facebook.com/LosAlamosNationalLab/>