Hi,
Have you tried using:
mpirun -ssi rpi sysv ...
or
mpirun -ssi rpi usysv ...
i.e.
use "shared memory" rather the default TCP/IP.
Regards
Neil
Ming Wu wrote:
> Hi,
>
> I assigned multiple processes on one machine instead of several machines. In this way, I expect the communication cost will be reduced compared with assigning them to several machines. However, the result is weird. both computation cost and communication cost are increased sharply, especially MPI_Reduce, MPI_Sendrecv. It seems that the underlying implementation of lam_mpi doesn't favor multiple processes on the same host.
>
> Your help will be greatly appreciated.
>
> thanks
>
> _______________________________________________
> This list is archived at http://www.lam-mpi.org/MailArchives/lam/
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