Dear openmpi developers, I'm wondering how to scatter the ranks across all compute nodes when they are spawned by a master processor.
I'm working on a cluster where Each node has two sockets, each socket is populated with a 16-core Haswell processor. Each core supports 2 hyper-threads. Whenever the spawned processors are less than the total number of cores (e.g. half of the core counts), I would like they are as spread as possible across all nodes such that I can use OMP threading on each rank. By default it seems the spawning will fill all 64 logical cores on one node before moving to the next node. It seems I can use the runtime parameter --map-by core:span to resolve this. Am I correct? However whenever I call MPI_spawn, I got the following runtime error. Could you advise how to proceed with this? [nid01876:62825] [[51146,0],0] ORTE_ERROR_LOG: Not found in file base/plm_base_receive.c at line 343 -------------------------------------------------------------------------- An internal error has occurred in ORTE: [[51146,0],0] FORCE-TERMINATE AT (null):1 - error base/plm_base_receive.c(344) This is something that should be reported to the developers.
