I have given this a shot. Using the two files testOctaveJulia.m and
testOctaveJulia.jl
testOctaveJulia.m:
if not(MPI_Initialized) MPI_Init; end
CW = MPI_Comm_Load("NEWORLD");
myrank = MPI_Comm_rank(CW);
commsize = MPI_Comm_size(CW);
sleep(myrank*0.5);
printf("I am Octave rank %d\n", myrank);
if myrank == 0
MPI_Send([5], 3, 0, CW);
endif
MPI_Barrier(CW);
MPI_Finalize();
testOctaveJulia.jl:
import MPI
function main()
MPI.Init()
comm = MPI.COMM_WORLD
rank = MPI.Comm_rank(comm)
commsize = MPI.Comm_size(comm)
sleep(rank*0.5)
println("I am Julia rank ", rank)
contrib = [0]
if rank==3
println("contrib before receive: ", contrib)
MPI.Recv!(contrib, 0, 0, comm)
println("contrib after receive: ", contrib)
end
MPI.Barrier(comm)
MPI.Finalize()
end
main()
I can launch using
mpirun -np 2 octave-cli --eval testOctaveJulia : -np 3 julia
testOctaveJulia.jl
The result is
michael@yosemite:~/Desktop/JO$ mpirun -np 2 octave-cli --eval
testOctaveJulia : -np 3 julia testOctaveJulia.jl
I am Octave rank 0
I am Octave rank 1
I am Julia rank 2
I am Julia rank 3
contrib before receive: [0]
contrib after receive: [2]
I am Julia rank 4
If you look at the two files, you'll see that rank 0, Octave, sends the a
scalar array containing the number 5 to rank 3. Rank 3 is a julia instance.
On rank 3, the variable contrib is initialized as a scalar array containing
0. After the receive, it contains a 2.
So... it seems to be possible to send messages from Octave to Julia, but
the contents are not received correctly. I suppose that Octave and Julia
have different methods of serializing contents when using MPI functions,
and that's something I don't know about. Any ideas?
Note, the Octave code requires the MPI wrappers
at http://octave.sourceforge.net/mpi/index.html
Julia is using MPI.jl on github. In my case, both are wrapping Open MPI
functions.
On Tuesday, April 5, 2016 at 11:30:33 AM UTC+2, michae...@gmail.com wrote:
>
> I use MPI with both Julia (using MPI.jl) and Octave (using the MPI package
> for Octave). For both Julia and Octave, the packages are wrapping (in my
> case) Open MPI functions. I believe that it should be possible for Julia
> and Octave to send information back and forth via MPI. Before trying this
> myself, does anyone have an example of something similar? Any pointers
> would be appreciated.
>
