You could do it by specifying which cores to use - something like mpirun -np 4 --slot-list 0-3 prog_1 : -np 1 prog_2
On Jun 6, 2013, at 1:52 AM, Nima Aghajari <gr...@gmx.net> wrote: > Dear all, > I am currently using openmpi 1.6.4 and trying to do a parallel performance > analysis for a parallel two-program mpirun. So what I have are two programs > that are executed like this: > > mpirun -np 4 my_prog1 : -np 1 my_prog2 > > my_prog1 and my_prog2 run sequentially, so when one program is actually doing > something the other one idles. So ideally I would like my_prog1 to use all 4 > available cores and my_prog2 could use any of those for but not an extra one! > The command from above results in a run with 5 mpi processes, which run on 5 > cores. But in order to compare it with another setup I have to restrict the > run to 4 actual cores. I tried using a hostfile as suggested in the > FAQ-examples: > > cat my_host > localhost slots=4 > mpirun -np 4 --hostfile my_host my_prog1 : -np 1 --hostfile my_host > my_prog2 > > This solution works fine for a single program mpirun. But for the multiple > program example from above it leads to a run on 5 cores again because of the > duplicate use of the hostfile. Does anyone have an idea how to restrict such > a mimd/mpmd mpirun to an overall number of cores? > _______________________________________________ > users mailing list > us...@open-mpi.org > http://www.open-mpi.org/mailman/listinfo.cgi/users