I've seen the same thing when I build openmpi 1.4.3 with Intel 12, but only when I have -O2 or -O3 in CFLAGS. If I drop it down to -O1 then the collectives hangs go away. I don't know what, if anything, the higher optimization buys you when compiling openmpi, so I'm not sure if that's an acceptable workaround or not.
My system is similar to yours - Intel X5570 with QDR Mellanox IB running RHEL 5, Slurm, and these openmpi btls: openib,sm,self. I'm using IMB 3.2.2 with a single iteration of Barrier to reproduce the hang, and it happens 100% of the time for me when I invoke it like this: # salloc -N 9 orterun -n 65 ./IMB-MPI1 -npmin 64 -iter 1 barrier The hang happens on the first Barrier (64 ranks) and each of the participating ranks have this backtrace: __poll (...) poll_dispatch () from [instdir]/lib/libopen-pal.so.0 opal_event_loop () from [instdir]/lib/libopen-pal.so.0 opal_progress () from [instdir]/lib/libopen-pal.so.0 ompi_request_default_wait_all () from [instdir]/lib/libmpi.so.0 ompi_coll_tuned_sendrecv_actual () from [instdir]/lib/libmpi.so.0 ompi_coll_tuned_barrier_intra_recursivedoubling () from [instdir]/lib/libmpi.so.0 ompi_coll_tuned_barrier_intra_dec_fixed () from [instdir]/lib/libmpi.so.0 PMPI_Barrier () from [instdir]/lib/libmpi.so.0 IMB_barrier () IMB_init_buffers_iter () main () The one non-participating rank has this backtrace: __poll (...) poll_dispatch () from [instdir]/lib/libopen-pal.so.0 opal_event_loop () from [instdir]/lib/libopen-pal.so.0 opal_progress () from [instdir]/lib/libopen-pal.so.0 ompi_request_default_wait_all () from [instdir]/lib/libmpi.so.0 ompi_coll_tuned_sendrecv_actual () from [instdir]/lib/libmpi.so.0 ompi_coll_tuned_barrier_intra_bruck () from [instdir]/lib/libmpi.so.0 ompi_coll_tuned_barrier_intra_dec_fixed () from [instdir]/lib/libmpi.so.0 PMPI_Barrier () from [instdir]/lib/libmpi.so.0 main () If I use more nodes I can get it to hang with 1ppn, so that seems to rule out the sm btl (or interactions with it) as a culprit at least. I can't reproduce this with openmpi 1.5.3, interestingly. -Marcus On 05/10/2011 03:37 AM, Salvatore Podda wrote: > Dear all, > > we succeed in building several version of openmpi from 1.2.8 to 1.4.3 > with Intel composer XE 2011 (aka 12.0). > However we found a threshold in the number of cores (depending from the > application: IMB, xhpl or user applications > and form the number of required cores) above which the application hangs > (sort of deadlocks). > The building of openmpi with 'gcc' and 'pgi' does not show the same limits. > There are any known incompatibilities of openmpi with this version of > intel compiilers? > > The characteristics of our computational infrastructure are: > > Intel processors E7330, E5345, E5530 e E5620 > > CentOS 5.3, CentOS 5.5. > > Intel composer XE 2011 > gcc 4.1.2 > pgi 10.2-1 > > Regards > > Salvatore Podda > > ENEA UTICT-HPC > Department for Computer Science Development and ICT > Facilities Laboratory for Science and High Performace Computing > C.R. Frascati > Via E. Fermi, 45 > PoBox 65 > 00044 Frascati (Rome) > Italy > > Tel: +39 06 9400 5342 > Fax: +39 06 9400 5551 > Fax: +39 06 9400 5735 > E-mail: salvatore.po...@enea.it > Home Page: www.cresco.enea.it > _______________________________________________ > users mailing list > us...@open-mpi.org > http://www.open-mpi.org/mailman/listinfo.cgi/users >
