[OMPI users] ISEND + IRECV in a cycle stuck

[Diego Avesani]

Dear all,

I have the following problem:

In my program each rank has a vector, where the position indicates where I
have to send the data.

For example for rank 0, I have:

*ALLOCATE(Ndata2send(0,MPI%nCPU-1)*

*Ndata2send(:) = 0,10,10,16*

where MPI%nCPU is the number of cPU, in my case 4

Thins means that I have to send 10 to rank 1, 10 to rank 2 and 16 to rank 3

I have the following cycle:

  icount=1
  DO iCPU=0,MPI%nCPU-1
     IF(iCPU.NE.MPI%rank)THEN
        iTag=iCPU
        CALL
MPI_ISEND(Ndata2send(iCPU),1,MPI_INTEGER,iCPU,iTag,MPI_COMM_WORLD,send_request(icount),MPI%iErr)
        icount=icount+1
     ENDIF
  ENDDO

  icount=1
  DO iCPU=0,MPI%nCPU-1
     IF(iCPU.NE.MPI%rank)THEN
        iTag=iCPU
        CALL
MPI_IRECV(Ndata2recv(iCPU),1,MPI_INTEGER,iCPU,iTag,MPI_COMM_WORLD,recv_request(icount),MPI%iErr)
        icount=icount+1
     ENDIF
  ENDDO

and then, to wait all comunication I have:

* CALL MPI_WAITALL(3,send_request,send_status_list,MPI%iErr)*
* CALL MPI_WAITALL(3,recv_request,recv_status_list,MPI%iErr)*


The problem is that comunication never stops.

Have I missed something? Please help me to understand what I havent't
understood.

Thanks





Diego