Hi Ralph, I was nodding whilst reading, until I got to PMIX_GROUP_LEAVE_REQUEST (Destruct procedure, PMIx_Groups). There are situations where a process will leave without the luxury of requesting and being patient first, e.g. faults (handled as termination, I know, bear with me a moment). If this event was instead PMIX_GROUP_LEFT, then processes would be written to be able to cope with sudden exits in other processes. They have to be written like that anyway because of PMIX_GROUP_NOTIFY_TERMINATION. This event simply distinguishes "the process called PMIx_GROUP_LEAVE" from "the RM figured out a process stopped executing (normally or abnormally)”. Is such a distinction useful? In terms of outstanding/in-progress collective operations, just state that calling PMIX_GROUP_LEAVE is not allowed unless no such operations are in flight. The potential race between a process calling PMIX_GROUP_LEAVE and other process(es) in the group starting a collective operation should not happen in a well-defined program. Also, if PMIX_GROUP_NOTIFY_TERMINATION can state "collective operations will be adjusted appropriately" then why can’t PMIX_GROUP_LEAVE say that too? — For PMIX_GROUP_JOIN, can the leader process give up creation of the group and somehow tell PMIX to stop trying? If so, then processes that accepted a join request should be informed that the group is never going to be constructed, i.e. they should stop waiting for the callback/return of the blocking function. Thus, "once the group has been completely constructed” could be tempered with “or the group construction fails”. Cheers, Dan. — Dr Daniel Holmes PhD Applications Consultant in HPC Research [email protected]<mailto:[email protected]> Phone: +44 (0) 131 651 3465 Mobile: +44 (0) 7940 524 088 Address: Room 3415, JCMB, The King’s Buildings, Edinburgh, EH9 3FD — The University of Edinburgh is a charitable body, registered in Scotland, with registration number SC005336. — On 8 Aug 2018, at 23:04, Ralph H Castain <[email protected]<mailto:[email protected]>> wrote: Hi folks I have updated the PMIx Group web page to capture the discussion of the prior meeting plus some subsequent thoughts: https://pmix.org/pmix-standard/pmix-groups/ I’ll try to put some initial implementation behind it before the meeting, so please feel free to chime up with any thoughts. Ralph On Aug 6, 2018, at 11:38 AM, Ralph H Castain <[email protected]<mailto:[email protected]>> wrote: Looks like I can free some time up this week for groups - will try to update later this week Sent from my iPhone On Aug 6, 2018, at 11:05 AM, HOLMES Daniel <[email protected]<mailto:[email protected]>> wrote:to Hi all, The next meeting for the Sessions WG will be *Tuesday 14th Aug 2018* at 12pm Eastern US time. Note the change of day and time. This is a one-off change due to vacation time. The connection details for the call will be sent out on this list nearer the time. Cheers, Dan. — Dr Daniel Holmes PhD Applications Consultant in HPC Research [email protected]<mailto:[email protected]> Phone: +44 (0) 131 651 3465 Mobile: +44 (0) 7940 524 088 Address: Room 3415, JCMB, The King’s Buildings, Edinburgh, EH9 3FD — The University of Edinburgh is a charitable body, registered in Scotland, with registration number SC005336. — The University of Edinburgh is a charitable body, registered in Scotland, with registration number SC005336. _______________________________________________ mpiwg-sessions mailing list [email protected]<mailto:[email protected]> https://lists.mpi-forum.org/mailman/listinfo/mpiwg-sessions _______________________________________________ mpiwg-sessions mailing list [email protected]<mailto:[email protected]> https://lists.mpi-forum.org/mailman/listinfo/mpiwg-sessions The University of Edinburgh is a charitable body, registered in Scotland, with registration number SC005336.