Probably yes, do I have a more systematic way? Thanks Claudio
2012/3/1, Jingcha Joba <pukkimon...@gmail.com>: > mpirun -np 4 --host node1,node2,node1,node2 ./app > > Is this what you want? > > On Thu, Mar 1, 2012 at 10:57 AM, Claudio Pastorino < > claudio.pastor...@gmail.com> wrote: > >> Dear all, >> I apologize in advance if this is not the right list to post this. I >> am a newcomer and please let me know if I should be sending this to >> another list. >> >> I program MPI trying to do HPC parallel programs. In particular I >> wrote a parallel code >> for molecular dynamics simulations. The program splits the work in a >> matrix of procs and >> I send messages along rows and columns in an equal basis. I learnt >> that the typical >> arrangement of cartesian topology is not usually the best option, >> because in a matrix, let's say of 4x4 procs with quad procs, the >> procs are arranged so that >> through columns one stays inside the same quad proc and through rows >> you are always going out to the network. This means procs are >> arranged as one quad per row. >> >> I try to explain this for a 2x2 case. The cartesian topology does this >> assignment, typically: >> cartesian mpi_comm_world >> 0,0 --> 0 >> 0,1 --> 1 >> 1,0 --> 2 >> 1,1 --> 3 >> The question is, how do I get a "user defined" assignment such as: >> 0,0 --> 0 >> 0,1 --> 2 >> 1,0 --> 1 >> 1,1 --> 3 >> >> ? >> >> Thanks in advance and I hope to have made this more or less >> understandable. >> Claudio >> _______________________________________________ >> users mailing list >> us...@open-mpi.org >> http://www.open-mpi.org/mailman/listinfo.cgi/users >> >
