PMI_RANK and PMI_SIZE look to me like what you want and one of my Intel colleagues had the same answer in response to a similar question regarding Intel MPI, which also uses Hydra ( https://software.intel.com/en-us/forums/intel-clusters-and-hpc-technology/to... ). I'm sure you know that all of this is non-standard and relying on it is inherently non-portable. Jeff On Sun, Feb 3, 2019 at 1:40 PM Brice Goglin via discuss <[email protected]> wrote:
Hello
Is there a way to find out the rank of a process (in COMM_WORLD) by looking at its environment? We use this feature in OpenMPI and srun for displaying the placement of ranks in hwloc tools. By default, we display the PID, but displaying the commworld rank is more useful. Looking in /proc/<pid>/environ is an easy way to find environment variables, but I could not find a clear solution for MPICH.
I tried on several machines with different mpich installations. In one case, I found a MPI_LOCALRANKID (which isn't exactly what I want but could be sufficient). There's also PMI_RANK, which may be identical to the commworld rank?
Thanks for the help
Brice
_______________________________________________ discuss mailing list [email protected] To manage subscription options or unsubscribe: https://lists.mpich.org/mailman/listinfo/discuss
-- Jeff Hammond [email protected] http://jeffhammond.github.io/