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hpcugent / vsc-mympirun

mympirun is a tool to facilitate running MPI programs on an HPC cluster
GNU General Public License v2.0
6 stars 9 forks source link

single-process mpi program gives error in multi-process env. #163

Open hajgato opened 4 years ago

hajgato commented 4 years ago

ml vsc-mympirun/5.0.0 mpifileutils/0.9.1-iimpi-2019a

[vsc43020@node3110 vsc43020]$ mypmirun --debug dcp -h
2020-01-16 13:41:50,394 DEBUG      mypmirun.ExtOption MainThread  changed loglevel to DEBUG, previous state: (mypmirun.mympirun.factory, NOTSET), (mypmirun.ExtOptionGroup, NOTSET), (mypmirun.vsc.utils.missing, NOTSET), (mypmirun.MypmirunOption, NOTSET), (mypmirun.ExtOption, NOTSET), (mypmirun.MympirunParser, NOTSET), (mypmirun, NOTSET)
2020-01-16 13:41:50,394 DEBUG      mypmirun.MypmirunOption MainThread  parseoptions: options from environment []
2020-01-16 13:41:50,394 DEBUG      mypmirun.MypmirunOption MainThread  parseoptions: options from commandline ['--debug', 'dcp', '-h']
2020-01-16 13:41:50,394 DEBUG      mypmirun.MypmirunOption MainThread  Found remaining args ['dcp', '-h']
2020-01-16 13:41:50,394 DEBUG      mypmirun.MypmirunOption MainThread  Found options {'help': None, 'setsched': None, 'logtofile': None, 'distribute': None, 'all_gpus': None, 'pass': [], 'debugmpi': False, 'info': False, 'multi': None, 'stats': 0, 'dry_run': False, 'debuglvl': 0, 'debug': True, 'hybrid': None, 'quiet': False, 'configfiles': None, 'showsched': False, 'print_launcher': None, 'ignoreconfigfiles': None, 'output': None, 'showmpi': False, 'setmpi': None} args ['dcp', '-h']
2020-01-16 13:41:50,395 DEBUG      mypmirun.MypmirunOption MainThread  Initialise case sensitive configparser
2020-01-16 13:41:50,395 DEBUG      mypmirun.MypmirunOption MainThread  parseconfigfiles: configfiles initially set []
2020-01-16 13:41:50,395 DEBUG      mypmirun.MypmirunOption MainThread  parseconfigfiles: configfiles set through commandline None
2020-01-16 13:41:50,395 DEBUG      mypmirun.MypmirunOption MainThread  parseconfigfiles: ignoreconfigfiles set through commandline None
2020-01-16 13:41:50,395 DEBUG      mypmirun.MypmirunOption MainThread  parseconfigfiles: following files were parsed []
2020-01-16 13:41:50,395 DEBUG      mypmirun.MypmirunOption MainThread  parseconfigfiles: following files were NOT parsed []
2020-01-16 13:41:50,395 DEBUG      mypmirun.MypmirunOption MainThread  parseconfigfiles: sections (w/o DEFAULT) []
2020-01-16 13:41:50,396 DEBUG      mypmirun.MypmirunOption MainThread  parseconfigfiles: no section MAIN
2020-01-16 13:41:50,396 DEBUG      mypmirun.MypmirunOption MainThread  parseconfigfiles: no section ('NO', 'SECTION')
2020-01-16 13:41:50,396 DEBUG      mypmirun.MypmirunOption MainThread  parseconfigfiles: going to parse options through cmdline []
2020-01-16 13:41:50,396 DEBUG      mypmirun.MympirunParser MainThread  Not processing environment for options
2020-01-16 13:41:50,396 DEBUG      mypmirun.MypmirunOption MainThread  parseconfigfiles: options from configfile []
2020-01-16 13:41:50,396 DEBUG      mypmirun.MypmirunOption MainThread  parseconfigfiles: parsed values from configfiles: {}
2020-01-16 13:41:50,396 DEBUG      mypmirun.MypmirunOption MainThread  final options: {'help': None, 'setsched': None, 'logtofile': None, 'distribute': None, 'all_gpus': None, 'pass': [], 'debugmpi': False, 'info': False, 'multi': None, 'stats': 0, 'dry_run': False, 'debuglvl': 0, 'debug': True, 'hybrid': None, 'quiet': False, 'configfiles': None, 'showsched': False, 'print_launcher': None, 'ignoreconfigfiles': None, 'output': None, 'showmpi': False, 'setmpi': None}
2020-01-16 13:41:50,396 DEBUG      mypmirun.MypmirunOption MainThread  mympirun will be executed by /apps/gent/CO7/skylake-ib/software/vsc-mympirun/5.0.0/bin/mypmirun
2020-01-16 13:41:50,397 DEBUG      mypmirun        MainThread  PATH before stripfake(): /apps/gent/CO7/skylake-ib/software/mpifileutils/0.9.1-iimpi-2019a/bin:/apps/gent/CO7/skylake-ib/software/libarchive/3.4.0-GCCcore-8.2.0/bin:/apps/gent/CO7/skylake-ib/software/bzip2/1.0.6-GCCcore-8.2.0/bin:/apps/gent/CO7/skylake-ib/software/attr/2.4.47-GCCcore-8.2.0/bin:/apps/gent/CO7/skylake-ib/software/impi/2018.4.274-iccifort-2019.1.144-GCC-8.2.0-2.31.1/bin64:/apps/gent/CO7/skylake-ib/software/ifort/2019.1.144-GCC-8.2.0-2.31.1/compilers_and_libraries_2019.1.144/linux/bin/intel64:/apps/gent/CO7/skylake-ib/software/icc/2019.1.144-GCC-8.2.0-2.31.1/compilers_and_libraries_2019.1.144/linux/bin/intel64:/apps/gent/CO7/skylake-ib/software/binutils/2.31.1-GCCcore-8.2.0/bin:/apps/gent/CO7/skylake-ib/software/GCCcore/8.2.0/bin:/apps/gent/CO7/skylake-ib/software/vsc-mympirun/5.0.0/bin/fake:/apps/gent/CO7/skylake-ib/software/vsc-mympirun/5.0.0/bin:/usr/libexec/slurm/wrapper:/usr/local/bin:/usr/bin:/usr/local/sbin:/usr/sbin:/opt/ibutils/bin
2020-01-16 13:41:50,399 DEBUG      mypmirun        MainThread  PATH after stripfake(): /apps/gent/CO7/skylake-ib/software/mpifileutils/0.9.1-iimpi-2019a/bin:/apps/gent/CO7/skylake-ib/software/libarchive/3.4.0-GCCcore-8.2.0/bin:/apps/gent/CO7/skylake-ib/software/bzip2/1.0.6-GCCcore-8.2.0/bin:/apps/gent/CO7/skylake-ib/software/attr/2.4.47-GCCcore-8.2.0/bin:/apps/gent/CO7/skylake-ib/software/impi/2018.4.274-iccifort-2019.1.144-GCC-8.2.0-2.31.1/bin64:/apps/gent/CO7/skylake-ib/software/ifort/2019.1.144-GCC-8.2.0-2.31.1/compilers_and_libraries_2019.1.144/linux/bin/intel64:/apps/gent/CO7/skylake-ib/software/icc/2019.1.144-GCC-8.2.0-2.31.1/compilers_and_libraries_2019.1.144/linux/bin/intel64:/apps/gent/CO7/skylake-ib/software/binutils/2.31.1-GCCcore-8.2.0/bin:/apps/gent/CO7/skylake-ib/software/GCCcore/8.2.0/bin:/apps/gent/CO7/skylake-ib/software/vsc-mympirun/5.0.0/bin:/usr/libexec/slurm/wrapper:/usr/local/bin:/usr/bin:/usr/local/sbin:/usr/sbin:/opt/ibutils/bin
2020-01-16 13:41:50,401 INFO       mypmirun        MainThread  Command mpirun found at /apps/gent/CO7/skylake-ib/software/impi/2018.4.274-iccifort-2019.1.144-GCC-8.2.0-2.31.1/bin64/mpirun
2020-01-16 13:41:50,402 DEBUG      mypmirun        MainThread  Checking whether <class 'vsc.mympirun.pmi.mpi.IntelMPI'> (MPI name: impi) matches /apps/gent/CO7/skylake-ib/software/impi/2018.4.274-iccifort-2019.1.144-GCC-8.2.0-2.31.1/bin64/mpirun
2020-01-16 13:41:50,403 DEBUG      mypmirun        MainThread  found mpi root: /apps/gent/CO7/skylake-ib/software/impi/2018.4.274-iccifort-2019.1.144-GCC-8.2.0-2.31.1
2020-01-16 13:41:50,405 DEBUG      mypmirun        MainThread  /apps/gent/CO7/skylake-ib/software/impi/2018.4.274-iccifort-2019.1.144-GCC-8.2.0-2.31.1/bin64/mpirun (real /kyukon/home/apps/CO7/skylake-ib/software/impi/2018.4.274-iccifort-2019.1.144-GCC-8.2.0-2.31.1/intel64/bin/mpirun) is in subdirectory of /kyukon/home/apps/CO7/skylake-ib/software/impi/2018.4.274-iccifort-2019.1.144-GCC-8.2.0-2.31.1
2020-01-16 13:41:50,407 DEBUG      mypmirun        MainThread  no mpirun version provided, skipping version check, match for <class 'vsc.mympirun.pmi.mpi.IntelMPI'>
2020-01-16 13:41:50,408 DEBUG      mypmirun.MypmirunOption MainThread  Found MPI classes [<class 'vsc.mympirun.pmi.mpi.IntelMPI'>, <class 'vsc.mympirun.pmi.mpi.OpenMPI4'>]
2020-01-16 13:41:50,408 DEBUG      mypmirun.MypmirunOption MainThread  Found Sched classes [<class 'slurm.Slurm'>]
2020-01-16 13:41:50,408 DEBUG      mypmirun.MypmirunOption MainThread  Found MPI class IntelMPI (scriptname mypmirun; isfake False)
2020-01-16 13:41:50,408 DEBUG      mypmirun.MypmirunOption MainThread  Found sched class Slurm from options.schedtype None (all Sched found Slurm)
2020-01-16 13:41:50,409 DEBUG      mypmirun.mympirun.factory MainThread  Created new Coupler (<class 'vsc.mympirun.factory.LogBase'>, <class 'vsc.mympirun.pmi.mpi.IntelMPI'>, <class 'slurm.Slurm'>) class for Coupler_IntelMPI_Slurm: 23018576
2020-01-16 13:41:50,410 DEBUG      mypmirun        MainThread  $EBROOTUCX not defined for UCX
2020-01-16 13:41:50,411 DEBUG      mypmirun.Coupler_IntelMPI_Slurm MainThread  No UCX root / version found
2020-01-16 13:41:50,412 DEBUG      mypmirun        MainThread  $EBROOTFCA not defined for FCA
2020-01-16 13:41:50,413 DEBUG      mypmirun.Coupler_IntelMPI_Slurm MainThread  No hcoll / FCA root / version found
2020-01-16 13:41:50,413 DEBUG      mypmirun.Coupler_IntelMPI_Slurm MainThread  No MPI-specific MPI tuning
2020-01-16 13:41:50,413 DEBUG      mypmirun.Coupler_IntelMPI_Slurm MainThread  No UCX found, so no UCX tuning
2020-01-16 13:41:50,414 DEBUG      mypmirun.Coupler_IntelMPI_Slurm MainThread  No hcoll found, no hcoll tuning
2020-01-16 13:41:50,414 DEBUG      mypmirun.Coupler_IntelMPI_Slurm MainThread  Calling mpi_tune
2020-01-16 13:41:50,414 DEBUG      mypmirun.Coupler_IntelMPI_Slurm MainThread  Found PMIv2 lib /usr/lib64/slurmpmi/libpmi.so from ['SLURM1', 'SYSTEM1', 'AUTOMATIC'] ({'SYSTEM2': '/usr/lib64/libpmi2.so', 'SLURM1': '/usr/lib64/slurmpmi/libpmi.so', 'SYSTEM1': '/usr/lib64/libpmi.so', 'AUTOMATIC': '/automatic/via/does/not/exist', 'SLURM2': '/usr/lib64/slurmpmi/libpmi2.so'})
2020-01-16 13:41:50,414 DEBUG      mypmirun.Coupler_IntelMPI_Slurm MainThread  Set environment variable I_MPI_PMI_LIBRARY: /usr/lib64/slurmpmi/libpmi.so
2020-01-16 13:41:50,414 DEBUG      mypmirun.Coupler_IntelMPI_Slurm MainThread  Calling mpi_pmi
2020-01-16 13:41:50,414 DEBUG      mypmirun.Coupler_IntelMPI_Slurm MainThread  Calling mpi_debug
2020-01-16 13:41:50,414 DEBUG      mypmirun.Coupler_IntelMPI_Slurm MainThread  Generated pmicmd sched arguments ['--chdir=/kyukon/scratch/gent/vo/000/gvo00002/vsc43020']
2020-01-16 13:41:50,414 DEBUG      mypmirun.Coupler_IntelMPI_Slurm MainThread  SLURM env variables SLURM_CLUSTERS=skitty, SLURM_CLUSTER_NAME=skitty, SLURM_CONF=/etc/slurm/slurm.conf_skitty, SLURM_CPUS_ON_NODE=1, SLURM_CPU_BIND=quiet,mask_cpu:0x000000001, SLURM_CPU_BIND_LIST=0x000000001, SLURM_CPU_BIND_TYPE=mask_cpu:, SLURM_CPU_BIND_VERBOSE=quiet, SLURM_GTIDS=0, SLURM_JOBID=515337, SLURM_JOB_ACCOUNT=gvo00002, SLURM_JOB_CPUS_PER_NODE=1(x8), SLURM_JOB_GID=2543020, SLURM_JOB_ID=515337, SLURM_JOB_NAME=INTERACTIVE, SLURM_JOB_NODELIST=node3110.skitty.os,node3111.skitty.os,node3112.skitty.os,node3113.skitty.os,node3114.skitty.os,node3115.skitty.os,node3138.skitty.os,node3139.skitty.os, SLURM_JOB_NUM_NODES=8, SLURM_JOB_PARTITION=skitty, SLURM_JOB_QOS=normal, SLURM_JOB_UID=2543020, SLURM_JOB_USER=vsc43020, SLURM_LAUNCH_NODE_IPADDR=10.141.10.65, SLURM_LOCALID=0, SLURM_MEM_PER_NODE=1024, SLURM_NNODES=8, SLURM_NODEID=0, SLURM_NODELIST=node3110.skitty.os,node3111.skitty.os,node3112.skitty.os,node3113.skitty.os,node3114.skitty.os,node3115.skitty.os,node3138.skitty.os,node3139.skitty.os, SLURM_NPROCS=8, SLURM_NTASKS=8, SLURM_NTASKS_PER_NODE=1, SLURM_PRIO_PROCESS=0, SLURM_PROCID=0, SLURM_PTY_PORT=35646, SLURM_PTY_WIN_COL=132, SLURM_PTY_WIN_ROW=30, SLURM_SRUN_COMM_HOST=10.141.10.65, SLURM_SRUN_COMM_PORT=35647, SLURM_STEPID=0, SLURM_STEP_ID=0, SLURM_STEP_LAUNCHER_PORT=35647, SLURM_STEP_NODELIST=node3110.skitty.os,node3111.skitty.os,node3112.skitty.os,node3113.skitty.os,node3114.skitty.os,node3115.skitty.os,node3138.skitty.os,node3139.skitty.os, SLURM_STEP_NUM_NODES=8, SLURM_STEP_NUM_TASKS=8, SLURM_STEP_TASKS_PER_NODE=1(x8), SLURM_SUBMIT_DIR=/kyukon/home/gent/430/vsc43020/BBTest, SLURM_SUBMIT_HOST=gligar05.gastly.os, SLURM_TASKS_PER_NODE=1(x8), SLURM_TASK_PID=37338, SLURM_TOPOLOGY_ADDR=node3110.skitty.os, SLURM_TOPOLOGY_ADDR_PATTERN=node, SLURM_UMASK=0002, SLURM_WORKING_CLUSTER=skitty:master27.skitty.os:6817:8704:109
2020-01-16 13:41:50,415 DEBUG      mypmirun.Coupler_IntelMPI_Slurm MainThread  Got job info 8 nodes; with per node 1 cores, 1 ranks, 1024 mem, None gpus
2020-01-16 13:41:50,415 DEBUG      mypmirun.Coupler_IntelMPI_Slurm MainThread  Got mpi size info 8 nodes; with per node 1 cores, 1 ranks, 1024 mem, None gpus
2020-01-16 13:41:50,416 DEBUG      mypmirun.Coupler_IntelMPI_Slurm MainThread  Unset environment variables SLURM_CPUS_ON_NODE=1 SLURM_CPU_BIND=quiet,mask_cpu:0x000000001 SLURM_CPU_BIND_LIST=0x000000001 SLURM_CPU_BIND_TYPE=mask_cpu: SLURM_CPU_BIND_VERBOSE=quiet SLURM_JOB_CPUS_PER_NODE=1(x8) SLURM_JOB_NUM_NODES=8 SLURM_LAUNCH_NODE_IPADDR=10.141.10.65 SLURM_MEM_PER_NODE=1024 SLURM_NNODES=8 SLURM_NODEID=0 SLURM_NPROCS=8 SLURM_NTASKS=8 SLURM_NTASKS_PER_NODE=1 SLURM_PRIO_PROCESS=0 SLURM_PROCID=0 SLURM_STEP_NUM_NODES=8 SLURM_STEP_NUM_TASKS=8 SLURM_STEP_TASKS_PER_NODE=1(x8) SLURM_TASKS_PER_NODE=1(x8) SLURM_TASK_PID=37338
2020-01-16 13:41:50,416 DEBUG      mypmirun.Coupler_IntelMPI_Slurm MainThread  Got pmi cmd args ['--nodes=8', '--ntasks=8', '--cpus-per-task=1', '--mem-per-cpu=1024']
2020-01-16 13:41:50,416 DEBUG      mypmirun.Coupler_IntelMPI_Slurm MainThread  Generated pmicmd sizing arguments ['--nodes=8', '--ntasks=8', '--cpus-per-task=1', '--mem-per-cpu=1024']
2020-01-16 13:41:50,416 DEBUG      mypmirun.Coupler_IntelMPI_Slurm MainThread  Generated pmicmd environment arguments ['--export=ALL']
2020-01-16 13:41:50,416 DEBUG      mypmirun.Coupler_IntelMPI_Slurm MainThread  Mapped PMI <class 'vsc.mympirun.pmi.pmi.PMIv2'> to flavour pmi2
2020-01-16 13:41:50,416 DEBUG      mypmirun.Coupler_IntelMPI_Slurm MainThread  Generated pmicmd mpi arguments ['--mpi=pmi2']
2020-01-16 13:41:50,416 DEBUG      mypmirun.Coupler_IntelMPI_Slurm MainThread  Generated pmicmd debug arguments []
2020-01-16 13:41:50,416 DEBUG      mypmirun.Coupler_IntelMPI_Slurm MainThread  Generated pmicmd ['srun', '--chdir=/kyukon/scratch/gent/vo/000/gvo00002/vsc43020', '--nodes=8', '--ntasks=8', '--cpus-per-task=1', '--mem-per-cpu=1024', '--export=ALL', '--mpi=pmi2']
2020-01-16 13:41:50,420 DEBUG      mypmirun.RunNoShellAsyncLoopStdout MainThread  _popen_named_args {'executable': None, 'shell': False, 'stdout': -1, 'close_fds': True, 'stdin': -1, 'stderr': -2}
2020-01-16 13:41:50,423 DEBUG      mypmirun.RunNoShellAsyncLoopStdout MainThread  _init_input: process stdin closed
2020-01-16 13:41:51,625 DEBUG      mypmirun.RunNoShellAsyncLoopStdout MainThread  _wait_for_process: loop stopped after 1 iterations (ec 1 loop_continue True)

Usage: dcp [options] source target
       dcp [options] source ... target_dir

Options:
  -i, --input <file>  - read source list from file
  -p, --preserve      - preserve permissions, ownership, timestamps, extended attributes
  -s, --synchronous   - use synchronous read/write calls (O_DIRECT)
  -S, --sparse        - create sparse files when possible
  -v, --verbose       - verbose output
  -q, --quiet         - quiet output
  -h, --help          - print usage
For more information see https://mpifileutils.readthedocs.io.

srun: error: node3111.skitty.os: task 1: Exited with exit code 1
srun: error: node3112.skitty.os: task 2: Exited with exit code 1
srun: error: node3110.skitty.os: task 0: Exited with exit code 1
srun: error: node3115.skitty.os: task 5: Exited with exit code 1
srun: error: node3139.skitty.os: task 7: Exited with exit code 1
srun: error: node3114.skitty.os: task 4: Exited with exit code 1
srun: error: node3138.skitty.os: task 6: Exited with exit code 1
srun: error: node3113.skitty.os: task 3: Exited with exit code 1
2020-01-16 13:41:51,629 ERROR      mypmirun.RunNoShellAsyncLoopStdout MainThread  _post_exitcode: problem occured with cmd ['srun', '--chdir=/kyukon/scratch/gent/vo/000/gvo00002/vsc43020', '--nodes=8', '--ntasks=8', '--cpus-per-task=1', '--mem-per-cpu=1024', '--export=ALL', '--mpi=pmi2', 'dcp', '-h']: (shellcmd ['srun', '--chdir=/kyukon/scratch/gent/vo/000/gvo00002/vsc43020', '--nodes=8', '--ntasks=8', '--cpus-per-task=1', '--mem-per-cpu=1024', '--export=ALL', '--mpi=pmi2', 'dcp', '-h']) output
Usage: dcp [options] source target
       dcp [options] source ... target_dir

Options:
  -i, --input <file>  - read source list from file
  -p, --preserve      - preserve permissions, ownership, timestamps, extended attributes
  -s, --synchronous   - use synchronous read/write calls (O_DIRECT)
  -S, --sparse        - create sparse files when possible
  -v, --verbose       - verbose output
  -q, --quiet         - quiet output
  -h, --help          - print usage
For more information see https://mpifileutils.readthedocs.io.

srun: error: node3111.skitty.os: task 1: Exited with exit code 1
srun: error: node3112.skitty.os: task 2: Exited with exit code 1
srun: error: node3110.skitty.os: task 0: Exited with exit code 1
srun: error: node3115.skitty.os: task 5: Exited with exit code 1
srun: error: node3139.skitty.os: task 7: Exited with exit code 1
srun: error: node3114.skitty.os: task 4: Exited with exit code 1
srun: error: node3138.skitty.os: task 6: Exited with exit code 1
srun: error: node3113.skitty.os: task 3: Exited with exit code 1

2020-01-16 13:41:51,633 WARNING    mypmirun.Coupler_IntelMPI_Slurm MainThread  main: exitcode 1 > 0; cmd ['srun', '--chdir=/kyukon/scratch/gent/vo/000/gvo00002/vsc43020', '--nodes=8', '--ntasks=8', '--cpus-per-task=1', '--mem-per-cpu=1024', '--export=ALL', '--mpi=pmi2', 'dcp', '-h']
2020-01-16 13:41:51,639 ERROR      mypmirun        MainThread  Main failed: main: exitcode 1 > 0; cmd ['srun', '--chdir=/kyukon/scratch/gent/vo/000/gvo00002/vsc43020', '--nodes=8', '--ntasks=8', '--cpus-per-task=1', '--mem-per-cpu=1024', '--export=ALL', '--mpi=pmi2', 'dcp', '-h']
Traceback (most recent call last):
  File "/kyukon/home/apps/CO7/skylake-ib/software/vsc-mympirun/5.0.0/lib/python2.7/site-packages/vsc_mympirun-5.0.0-py2.7.egg/vsc/mympirun/main.py", line 120, in main
    instance.main()
  File "/kyukon/home/apps/CO7/skylake-ib/software/vsc-mympirun/5.0.0/lib/python2.7/site-packages/vsc_mympirun-5.0.0-py2.7.egg/vsc/mympirun/pmi/mpi.py", line 98, in main
    self.log.raiseException("main: exitcode %s > 0; cmd %s" % (exitcode, cmd))
  File "/kyukon/home/apps/CO7/skylake-ib/software/vsc-mympirun/5.0.0/lib/python2.7/site-packages/vsc_base-2.9.3-py2.7.egg/vsc/utils/fancylogger.py", line 333, in raiseException
    raise err
Exception: main: exitcode 1 > 0; cmd ['srun', '--chdir=/kyukon/scratch/gent/vo/000/gvo00002/vsc43020', '--nodes=8', '--ntasks=8', '--cpus-per-task=1', '--mem-per-cpu=1024', '--export=ALL', '--mpi=pmi2', 'dcp', '-h']
boegel commented 4 years ago

That's just because dcp -h exits with a non-zero exit code though...

There's nothing much we can do about this, other than ask the dcp developers to change this (-h or --help should not exit with non-zero exit code)?