Big MPI---point-to-point functionality (MPI_Count + miscellaneous)

[tonyskjellum]

Problem

For 64-bit clean functionality, convenience, and symmetry, the Big MPI principles being applied in Ticket #80 to collective operations should be applied to MPI point-to-point functionality.

Proposal

MPI needs to be 64-bit clean throughout.

Changes to the Text

MPI_Count will replace int for counts; support counts > 2^31

Other checks of any non-64-bit-clean features in point-to-point after review.

This ticket does not address the MPI_Rank issue; that is a separate, cross-cutting ticket.

Impact on Implementations

No current API is impacted. New _X APIs for all point-to-point operations affected will be needed.

MPI implementations will have to be 64-bit clean inside since count*extent > 2^31 is already problematic for some implementations. New APIs will have to be added and the internals of MPI will have to be 64-bit capable for buffers and related issues.

Impact on Users

Users who opt in with the new API will be able to send and receive larger messages [MPI_Count]

References

See also Ticket #80, #97, #98, #99

PR https://github.com/mpi-forum/mpi-standard/pull/60

[tonyskjellum]

Here is the initial text for the pull request:

mpi32-report-ticket100-pt2pt-20sep18-1641.pdf

[wesbland]

@tonyskjellum / @puribangalore - Is this issue replaced by #137? Can we close this?

[puribangalore]

Yes.

…

On Wed, Oct 7, 2020 at 10:34 AM Wesley Bland ***@***.***> wrote: @tonyskjellum <https://github.com/tonyskjellum> / @puribangalore <https://github.com/puribangalore> - Is this issue replaced by #137 <#137>? Can we close this? — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#100 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AD2CIBK6R77I3QLWI44ZHVLSJSC77ANCNFSM4FFAQTOQ> .