What is the purpose fo using -rr and -grr round robin options of mpiexec utility ?

[ArthurRatz]

Dear Collegues, I've got a question for you : what is the purpose fo using -rr and -grr round robin options of mpiexec utility ?

Thanks in advance.

Cheers, Arthur.

[Artem_R_Intel1]

Hi Arthur,

According to the Intel® MPI Library for Linux* OS Reference Manual:

-perhost <# of processes >, -ppn <# of processes >, or -grr <# of processes>
Use this option to place the indicated number of consecutive MPI processes on every host in the group using round robin scheduling. See the I_MPI_PERHOST environment variable for more details.
-rr
Use this option to place consecutive MPI processes on different hosts using the round robin scheduling. This option is equivalent to -perhost 1. See the I_MPI_PERHOST environment variable for more details.

[ArthurRatz]

Thanks for your reply.