Python mpi4py.MPI 模块，Get_processor_name() 实例源码

def main():
    """
    main entry point for script
    """

    comm = MPI.COMM_WORLD

    opts = getoptions(True)

    opts['threads'] = comm.Get_size()

    logout = "mpiOutput-{}.log".format(comm.Get_rank())

    # For MPI jobs, do something sane with logging.
    setuplogger(logging.ERROR, logout, opts['log'])

    config = Config()

    if comm.Get_size() < 2:
        logging.error("Must run MPI job with at least 2 processes")
        sys.exit(1)

    myhost = MPI.Get_processor_name()
    logging.info("Nodename: %s", myhost)

    processjobs(config, opts, comm.Get_rank(), comm)

    logging.info("Rank: %s FINISHED", comm.Get_rank())

def get_device(comm, num_masters=1, gpu_limit=-1, gpu_for_master=False):
    """Arguments:
        comm: MPI intracommunicator containing all processes
        num_masters: number of processes that will be assigned as masters
        gpu_limit: maximum number of gpus to use on one host
        gpu_for_master: whether master processes should be given a gpu
       Returns device name 'cpu' or 'gpuN' appropriate for use with theano""" 
    rank = comm.Get_rank()
    if gpu_for_master:
        gpu_ranks = range(comm.Get_size())
    else:
        gpu_ranks = get_worker_ranks( comm, num_masters )

    # Get the ranks of the other processes that share the same host
    # and determine which GPU to take on the host
    host = MPI.Get_processor_name()
    hosts = comm.allgather(host)
    workers_sharing_host = [ i for i in gpu_ranks
            if hosts[i] == host ]
    if rank in workers_sharing_host:
        worker_id = workers_sharing_host.index( rank )
    else:
        worker_id = -1

    # get_num_gpus will fail if CUDA is not installed, so we short circuit if 0 GPUs are requested
    if gpu_limit == 0:
        return 'cpu'
    max_gpu = get_num_gpus() - 1
    if gpu_limit > 0:
        max_gpu = min( max_gpu, gpu_limit-1 )
    if worker_id < 0:# or worker_id > max_gpu:
        return 'cpu'
    else:
        return 'gpu%d' % (worker_id%(max_gpu+1))

def get_id_within_node(comm=None):
    from mpi4py import MPI
    if comm is None: comm = MPI.COMM_WORLD
    rank = comm.rank
    nodename =  MPI.Get_processor_name()
    nodelist = comm.allgather(nodename)
    return len([i for i in nodelist[:rank] if i==nodename])

def __init__(self, parallel=True, capture=False, print_worker_log=True):

        if run_mpi == False:
            print "NewParallel warning: mpi4py could not be loaded"
            print "\tany instances of NewParallel will run in serial"
            self.parallel = False
        else:
            self.parallel = parallel

        self.capture = capture
        self.print_worker_log=print_worker_log

        if self.parallel:

            self.processor_name = MPI.Get_processor_name()

            self.comm = MPI.COMM_WORLD
            self.size = self.comm.Get_size()
            self.rank = self.comm.Get_rank()

            self.status = MPI.Status()

            # define MPI message tags
            self.tags = enum('READY', 'DONE', 'EXIT', 'START', 'ERROR')

            if self.size == 1:
                self.parallel = False
                print "NewParallel warning: only one core found"
                print "\tany instances of NewParallel will run in serial"

        else:
            self.size = 1
            self.rank = 0


        self.task_count = 0
        self.task_list = None

        self.use_master_update = False
        self.update_interval = None

def spawn_load(self):

        '''spwan a parallel loading process using MPI'''

        if not para_load:
            return

        from mpi4py import MPI
        import os
        import sys

        hostname = MPI.Get_processor_name()
        mpiinfo = MPI.Info.Create()

        # will give all nodes filled issue if use key=host because need an additional slot
        # also the hostname should be exactly the same in the output list of --display-allocation
        if hostname != hostname.split('.')[0]:
            hostname = hostname.split('.')[0]
        mpiinfo.Set(key = 'add-host',value = hostname)

        num_spawn = 1

        if "CPULIST_train" in os.environ:
        # see https://gist.github.com/lebedov/eadce02a320d10f0e81c
            # print os.environ['CPULIST_train']
            envstr=""
            # for key, value in dict(os.environ).iteritems():
            #     envstr+= '%s=%s\n' % (key,value)
            envstr+='CPULIST_train=%s\n' %  os.environ['CPULIST_train']
            mpiinfo.Set(key ='env', value = envstr)


        ninfo = mpiinfo.Get_nkeys()
        # print ninfo

        mpicommand = sys.executable

        file_dir = os.path.dirname(os.path.realpath(__file__))# get the dir of imagenet.py

        self.icomm= MPI.COMM_SELF.Spawn(mpicommand, 
                args=[file_dir+'/proc_load_mpi.py'],
                info = mpiinfo, maxprocs = num_spawn)