I don't see where you told OMPI to --bind-to-core. We don't automatically bind, so you have to explicitly tell us to do so.
On Mar 23, 2012, at 6:20 AM, Pavel Mezentsev wrote: > Hello > > I'm doing some testing with IMB and dicovered a strange thing: > > Since I have a system with new AMD opteron 6276 processors I'm using 1.5.5rc3 > since it supports binding to cores. > > But when I run the barrier test form intel mpi benchmarks, the best I get is: > #repetitions t_min[usec] t_max[usec] t_avg[usec] > 598 15159.56 15211.05 15184.70 > (/opt/openmpi-1.5.5rc3/intel12/bin/mpirun -x OMP_NUM_THREADS=1 -hostfile > hosts_all2all_2 -npernode 32 --mca btl openib,sm,self -mca > coll_tuned_use_dynamic_rules 1 -mca coll_tuned_barrier_algorithm 1 -np 256 > openmpi-1.5.5rc3/intel12/IMB-MPI1 -off_cache 16,64 -msglog 1:16 -npmin 256 > barrier) > > And with openmpi 1.5.4 the result is much better: > #repetitions t_min[usec] t_max[usec] t_avg[usec] > 1000 113.23 113.33 113.28 > > (/opt/openmpi-1.5.4/intel12/bin/mpirun -x OMP_NUM_THREADS=1 -hostfile > hosts_all2all_2 -npernode 32 --mca btl openib,sm,self -mca > coll_tuned_use_dynamic_rules 1 -mca coll_tuned_barrier_algorithm 3 -np 256 > openmpi-1.5.4/intel12/IMB-MPI1 -off_cache 16,64 -msglog 1:16 -npmin 256 > barrier) > > and still I couldn't come close to the result I got with mvapich: > #repetitions t_min[usec] t_max[usec] t_avg[usec] > 1000 17.51 17.53 17.53 > > (/opt/mvapich2-1.8/intel12/bin/mpiexec.hydra -env OMP_NUM_THREADS 1 -hostfile > hosts_all2all_2 -np 256 mvapich2-1.8/intel12/IMB-MPI1 -mem 2 -off_cache 16,64 > -msglog 1:16 -npmin 256 barrier) > > I dunno if this is a bug or me doing something not the way I should. So is > there a way to improve my results? > > Best regards, > Pavel Mezentsev > > > _______________________________________________ > devel mailing list > de...@open-mpi.org > http://www.open-mpi.org/mailman/listinfo.cgi/devel
