On Jun 4, 2008, at 10:39 AM, tayfun sen wrote:
I would like to run an OpenMPI application on one node and since I
think
it would be better performance wise I want it to use shared memory for
communication and not tcp. Is it possible to use shared memory not
only
for MPI communication but also for control messages and other similar
inner MPI related communication? (so no tcp communication whatsoever
is
used).
I'm afraid not -- the only "oob" component ("out of band", meaning
"not user-level MPI communication") that we have written is the TCP
component. We've toyed with the idea of writing others, but have
never done it.
The oob component is mainly used during process startup and shutdown.
So it doesn't really affect your steady-state MPI performance.
# mpirun --host localhost --mca btl sm,self --mca oob ^tcp -n 2 hello
[myhost:08491] [NO-NAME] ORTE_ERROR_LOG: Not found in file
runtime/orte_init_stage1.c at line 182
--------------------------------------------------------------------------
It looks like orte_init failed for some reason; your parallel
process is
[snip]
This is OMPI's way of telling you that by deselecting the tcp oob, it
can't find any others to use.
--
Jeff Squyres
Cisco Systems
