Hi Rolf, thanks for your input. You're right, I miss the coll_tuned_use_dynamic_rules option.
I'll check if I the segmentation fault disappears when using the basic bcast linear algorithm using the proper command line you provided. Regards, Eloi On Tuesday 13 July 2010 20:39:59 Rolf vandeVaart wrote: > Hi Eloi: > To select the different bcast algorithms, you need to add an extra mca > parameter that tells the library to use dynamic selection. > --mca coll_tuned_use_dynamic_rules 1 > > One way to make sure you are typing this in correctly is to use it with > ompi_info. Do the following: > ompi_info -mca coll_tuned_use_dynamic_rules 1 --param coll > > You should see lots of output with all the different algorithms that can > be selected for the various collectives. > Therefore, you need this: > > --mca coll_tuned_use_dynamic_rules 1 --mca coll_tuned_bcast_algorithm 1 > > Rolf > > On 07/13/10 11:28, Eloi Gaudry wrote: > > Hi, > > > > I've found that "--mca coll_tuned_bcast_algorithm 1" allowed to switch to > > the basic linear algorithm. Anyway whatever the algorithm used, the > > segmentation fault remains. > > > > Does anyone could give some advice on ways to diagnose the issue I'm > > facing ? > > > > Regards, > > Eloi > > > > On Monday 12 July 2010 10:53:58 Eloi Gaudry wrote: > >> Hi, > >> > >> I'm focusing on the MPI_Bcast routine that seems to randomly segfault > >> when using the openib btl. I'd like to know if there is any way to make > >> OpenMPI switch to a different algorithm than the default one being > >> selected for MPI_Bcast. > >> > >> Thanks for your help, > >> Eloi > >> > >> On Friday 02 July 2010 11:06:52 Eloi Gaudry wrote: > >>> Hi, > >>> > >>> I'm observing a random segmentation fault during an internode parallel > >>> computation involving the openib btl and OpenMPI-1.4.2 (the same issue > >>> can be observed with OpenMPI-1.3.3). > >>> > >>> mpirun (Open MPI) 1.4.2 > >>> Report bugs to http://www.open-mpi.org/community/help/ > >>> [pbn08:02624] *** Process received signal *** > >>> [pbn08:02624] Signal: Segmentation fault (11) > >>> [pbn08:02624] Signal code: Address not mapped (1) > >>> [pbn08:02624] Failing at address: (nil) > >>> [pbn08:02624] [ 0] /lib64/libpthread.so.0 [0x349540e4c0] > >>> [pbn08:02624] *** End of error message *** > >>> sh: line 1: 2624 Segmentation fault > >>> > >>> \/share\/hpc3\/actran_suite\/Actran_11\.0\.rc2\.41872\/RedHatEL\-5\/x86 > >>> _6 4\ /bin\/actranpy_mp > >>> '--apl=/share/hpc3/actran_suite/Actran_11.0.rc2.41872/RedHatEL-5/x86_64 > >>> /A c tran_11.0.rc2.41872' > >>> '--inputfile=/work/st25652/LSF_130073_0_47696_0/Case1_3Dreal_m4_n2.dat' > >>> '--scratch=/scratch/st25652/LSF_130073_0_47696_0/scratch' '--mem=3200' > >>> '--threads=1' '--errorlevel=FATAL' '--t_max=0.1' '--parallel=domain' > >>> > >>> If I choose not to use the openib btl (by using --mca btl self,sm,tcp > >>> on the command line, for instance), I don't encounter any problem and > >>> the parallel computation runs flawlessly. > >>> > >>> I would like to get some help to be able: > >>> - to diagnose the issue I'm facing with the openib btl > >>> - understand why this issue is observed only when using the openib btl > >>> and not when using self,sm,tcp > >>> > >>> Any help would be very much appreciated. > >>> > >>> The outputs of ompi_info and the configure scripts of OpenMPI are > >>> enclosed to this email, and some information on the infiniband drivers > >>> as well. > >>> > >>> Here is the command line used when launching a parallel computation > >>> > >>> using infiniband: > >>> path_to_openmpi/bin/mpirun -np $NPROCESS --hostfile host.list --mca > >>> > >>> btl openib,sm,self,tcp --display-map --verbose --version --mca > >>> mpi_warn_on_fork 0 --mca btl_openib_want_fork_support 0 [...] > >>> > >>> and the command line used if not using infiniband: > >>> path_to_openmpi/bin/mpirun -np $NPROCESS --hostfile host.list --mca > >>> > >>> btl self,sm,tcp --display-map --verbose --version --mca > >>> mpi_warn_on_fork 0 --mca btl_openib_want_fork_support 0 [...] > >>> > >>> Thanks, > >>> Eloi > > > > _______________________________________________ > > users mailing list > > us...@open-mpi.org > > http://www.open-mpi.org/mailman/listinfo.cgi/users -- Eloi Gaudry Free Field Technologies Company Website: http://www.fft.be Company Phone: +32 10 487 959
