Thanks for the tip. I can't tell yet whether it helped or not. However, with your settings I get the following warning: WARNING: Open MPI will create a shared memory backing file in a directory that appears to be mounted on a network filesystem.
I repeated the run with my settings and I noticed that on at least one node my app didn't came up. I can see an orted daemon on this node, but no other process. And this was 30 minutes after the app started. orted -mca ess tm -mca orte_ess_jobid 125894656 -mca orte_ess_vpid 63 -mc a orte_ess_num_procs 255 --hnp-uri ... Thorsten On Wednesday, June 22, 2011, Gilbert Grosdidier wrote: > Bonjour Thorsten, > > I'm not surprised about the cluster type, indeed, > but I do not remember getting such specific hang up you mention. > > Anyway, I suspect SGI Altix is a little bit special for OpenMPI, > and I usually run with the following setup: > - there is need to create for each job a specific tmp area, > like "/scratch/ggg/uuu/run/tmp/pbs.${PBS_JOBID}" > - then use something like that: > > setenv TMPDIR "/scratch/ggg/uuu/run/tmp/pbs.${PBS_JOBID}" > setenv OMPI_PREFIX_ENV "/scratch/ggg/uuu/run/tmp/pbs.${PBS_JOBID}" > setenv OMPI_MCA_mpi_leave_pinned_pipeline 1 > > - then, for running, many of these -mca options are probably useless > with your app, > while many of them may show to be useful. Your own way ... > > mpiexec -mca coll_tuned_use_dynamic_rules 1 -hostfile $PBS_NODEFILE - > mca rmaps seq -mca btl_openib_rdma_pipeline_send_length 65536 -mca > btl_openib_rdma_pipeline_frag_size 65536 -mca > btl_openib_min_rdma_pipeline_size 65536 -mca > btl_self_rdma_pipeline_send_length 262144 -mca > btl_self_rdma_pipeline_frag_size 262144 -mca plm_rsh_num_concurrent > 4096 -mca mpi_paffinity_alone 1 -mca mpi_leave_pinned_pipeline 1 -mca > btl_sm_max_send_size 128 -mca > coll_tuned_pre_allocate_memory_comm_size_limit 1048576 -mca > btl_openib_cq_size 128 -mca btl_ofud_rd_num 128 -mca > mpi_preconnect_mpi 0 -mca mpool_sm_min_size 131072 -mca btl > sm,openib,self -mca btl_openib_want_fork_support 0 -mca > opal_set_max_sys_limits 1 -mca osc_pt2pt_no_locks 1 -mca > osc_rdma_no_locks 1 YOUR_APP > > (Watch the step : only one line only ...) > > This should be suitable for up to 8k cores. > > > HTH, Best, G. > > Le 22 juin 11 à 09:13, Thorsten Schuett a écrit : > > Sure. It's an SGI ICE cluster with dual-rail IB. The HCAs are Mellanox > > ConnectX IB DDR. > > > > This is a 2040 cores job. I use 255 nodes with one MPI task on each > > node and > > use 8-way OpenMP. > > > > I don't need -np and -machinefile, because mpiexec picks up this > > information > > from PBS. > > > > Thorsten > > > > On Tuesday, June 21, 2011, Gilbert Grosdidier wrote: > >> Bonjour Thorsten, > >> > >> Could you please be a little bit more specific about the cluster > >> > >> itself ? > >> > >> G. > >> > >> Le 21 juin 11 à 17:46, Thorsten Schuett a écrit : > >>> Hi, > >>> > >>> I am running openmpi 1.5.3 on a IB cluster and I have problems > >>> starting jobs > >>> on larger node counts. With small numbers of tasks, it usually > >>> works. But now > >>> the startup failed three times in a row using 255 nodes. I am using > >>> 255 nodes > >>> with one MPI task per node and the mpiexec looks as follows: > >>> > >>> mpiexec --mca btl self,openib --mca mpi_leave_pinned 0 ./a.out > >>> > >>> After ten minutes, I pulled a stracktrace on all nodes and killed > >>> the job, > >>> because there was no progress. In the following, you will find the > >>> stack trace > >>> generated with gdb thread apply all bt. The backtrace looks > >>> basically the same > >>> on all nodes. It seems to hang in mpi_init. > >>> > >>> Any help is appreciated, > >>> > >>> Thorsten > >>> > >>> Thread 3 (Thread 46914544122176 (LWP 28979)): > >>> #0 0x00002b6ee912d9a2 in select () from /lib64/libc.so.6 > >>> #1 0x00002b6eeabd928d in service_thread_start (context=<value > >>> optimized out>) > >>> at btl_openib_fd.c:427 > >>> #2 0x00002b6ee835e143 in start_thread () from /lib64/ > >>> libpthread.so.0 > >>> #3 0x00002b6ee9133b8d in clone () from /lib64/libc.so.6 > >>> #4 0x0000000000000000 in ?? () > >>> > >>> Thread 2 (Thread 46916594338112 (LWP 28980)): > >>> #0 0x00002b6ee912b8b6 in poll () from /lib64/libc.so.6 > >>> #1 0x00002b6eeabd7b8a in btl_openib_async_thread (async=<value > >>> optimized > >>> out>) at btl_openib_async.c:419 > >>> #2 0x00002b6ee835e143 in start_thread () from /lib64/ > >>> libpthread.so.0 > >>> #3 0x00002b6ee9133b8d in clone () from /lib64/libc.so.6 > >>> #4 0x0000000000000000 in ?? () > >>> > >>> Thread 1 (Thread 47755361533088 (LWP 28978)): > >>> #0 0x00002b6ee9133fa8 in epoll_wait () from /lib64/libc.so.6 > >>> #1 0x00002b6ee87745db in epoll_dispatch (base=0xb79050, > >>> arg=0xb558c0, > >>> tv=<value optimized out>) at epoll.c:215 > >>> #2 0x00002b6ee8773309 in opal_event_base_loop (base=0xb79050, > >>> flags=<value > >>> optimized out>) at event.c:838 > >>> #3 0x00002b6ee875ee92 in opal_progress () at runtime/ > >>> opal_progress.c:189 > >>> #4 0x0000000039f00001 in ?? () > >>> #5 0x00002b6ee87979c9 in std::ios_base::Init::~Init () at > >>> ../../.././libstdc++-v3/src/ios_init.cc:123 > >>> #6 0x00007fffc32c8cc8 in ?? () > >>> #7 0x00002b6ee9d20955 in orte_grpcomm_bad_get_proc_attr > >>> (proc=<value > >>> optimized out>, attribute_name=0x2b6ee88e5780 " \020322351n+", > >>> val=0x2b6ee875ee92, size=0x7fffc32c8cd0) at grpcomm_bad_module.c:500 > >>> #8 0x00002b6ee86dd511 in ompi_modex_recv_key_value (key=<value > >>> optimized > >>> out>, source_proc=<value optimized out>, value=0xbb3a00, dtype=14 > >>> '\016') at > >>> runtime/ompi_module_exchange.c:125 > >>> #9 0x00002b6ee86d7ea1 in ompi_proc_set_arch () at proc/proc.c:154 > >>> #10 0x00002b6ee86db1b0 in ompi_mpi_init (argc=15, > >>> argv=0x7fffc32c92f8, > >>> requested=<value optimized out>, provided=0x7fffc32c917c) at > >>> runtime/ompi_mpi_init.c:699 > >>> #11 0x00007fffc32c8e88 in ?? () > >>> #12 0x00002b6ee77f8348 in ?? () > >>> #13 0x00007fffc32c8e60 in ?? () > >>> #14 0x00007fffc32c8e20 in ?? () > >>> #15 0x0000000009efa994 in ?? () > >>> #16 0x0000000000000000 in ?? () > >>> _______________________________________________ > >>> users mailing list > >>> us...@open-mpi.org > >>> http://www.open-mpi.org/mailman/listinfo.cgi/users > >> > >> -- > >> *---------------------------------------------------------------------* > >> > >> Gilbert Grosdidier gilbert.grosdid...@in2p3.fr > >> LAL / IN2P3 / CNRS Phone : +33 1 6446 8909 > >> Faculté des Sciences, Bat. 200 Fax : +33 1 6446 8546 > >> B.P. 34, F-91898 Orsay Cedex (FRANCE) > >> > >> *---------------------------------------------------------------------* > > > > _______________________________________________ > > users mailing list > > us...@open-mpi.org > > http://www.open-mpi.org/mailman/listinfo.cgi/users > > -- > *---------------------------------------------------------------------* > Gilbert Grosdidier gilbert.grosdid...@in2p3.fr > LAL / IN2P3 / CNRS Phone : +33 1 6446 8909 > Faculté des Sciences, Bat. 200 Fax : +33 1 6446 8546 > B.P. 34, F-91898 Orsay Cedex (FRANCE) > *---------------------------------------------------------------------*