nonblocking sendrecv

[brandongc]

I would like to propose adding a nonblocking sendrecv. This is different from MPI_ISEND + MPI_IRECV + MPI_WAITALL in that 1 fewer request is involved and is far more convenient for developers who wish to convert blocking code to nonblocking. Additionally there are not persistent versions currently.

At a minimum I would like to add:

• MPI_ISENDRECV
• MPI_ISENDRECV_REPLACE

Persistent versions would involve adding:

• MPI_SENDRECV_INIT
• MPI_SENDRECV_REPLACE_INIT

If people think it is a good idea I can to put the relevant text together in a branch. Is there a place for that under https://github.com/mpiwg-p2p? or do I need some additional permissions somewhere?

[dholmes-epcc-ed-ac-uk]

Thanks for volunteering, @brandongc!

Full instructions on how to contribute are provided in the wiki for the MPI Forum Github repository:
https://github.com/mpi-forum/mpi-issues/wiki

I can walk you through the process, if needed.

You will need access to the MPI Forum private Github repository, see:
https://github.com/mpi-forum/mpi-issues/wiki/Access-to-the-MPI-Forum-private-repository

[brandongc]

I have made a branch "nonblocking-sendrecv" under mpiwg-ptp/mpi-standard

[dholmes-epcc-ed-ac-uk]

Thanks - good work :)

I've made your branch into PR#104:
https://github.com/mpi-forum/mpi-standard/pull/104
and linked it to issue#125:
mpi-forum/mpi-issues#125