[mpi-21] Ballot 4 - Re: Re: SEND COUNT and RECEIVE COUNT

Rolf Rabenseifner rabenseifner at [hidden]
Mon Jan 28 08:44:19 CST 2008



Bill, 
please can you forward this to Yukiya Aoyama <aoyama_at_...>,
the originator of this track.
Thanks, Rolf
___________________________________
This is a proposal for MPI 2.1, Ballot 4.

This is a follow up to:
  Description of the send and receive count arguments to MPI_Alltoallv 
  in http://www.cs.uiuc.edu/homes/wgropp/projects/parallel/MPI/mpi-errata/index.html
with mail discussion in
  http://www.cs.uiuc.edu/homes/wgropp/projects/parallel/MPI/mpi-errata/discuss/alltoallv/

Based on the questions for clarification, I propose not to include
any further clarification into the standard.

Reason:
MPI-1, Sect. 4.8, MPI_ALLTOALLV, page 112, lines 37-40 clearly states:

  "The type signature associated with sendcount[j], sendtype at 
  process i must be equal to the type signature associated with 
  recvcount[i], recvtype at process j. This implies that the amount 
  of data sent must be equal to the amount of data received, pairwise 
  between every pair of processes. Distinct type maps between sender 
  and receiver are still allowed."

The same text is also used for 
MPI-2.0, Sect. 7.3.5 MPI_ALLTOALLW, page 165, lines 42-45.

Okay?

Best regards
Rolf

Dr. Rolf Rabenseifner . . . . . . . . . .. email rabenseifner_at_[hidden]
High Performance Computing Center (HLRS) . phone ++49(0)711/685-65530
University of Stuttgart . . . . . . . . .. fax ++49(0)711 / 685-65832
Head of Dpmt Parallel Computing . . . www.hlrs.de/people/rabenseifner
Nobelstr. 19, D-70550 Stuttgart, Germany . (Office: Allmandring 30)



More information about the Mpi-21 mailing list