Exemplo n.º 1
0
    def _create_subcomm(self):
        """
        Internal function to create the sub-communicator that will be 
        used by each independent worker when running the task function
        
        Notes
        -----
        This function updates the global ``nbodykit`` communicator
        via ``set_nbkit_comm`` so all plugins will be initialized 
        with this sub-communicator
        """
        self.subcomm = None
        chain_ranks = []
        color = 0
        total_ranks = 0

        # split the ranks
        for i, ranks in split_ranks(self.size,
                                    self.cpus_per_worker,
                                    include_all=self.use_all_cpus):
            chain_ranks.append(ranks[0])
            if self.rank in ranks: color = i + 1
            total_ranks += len(ranks)

        self.workers = i + 1  # store the total number of workers
        leftover = (self.size - 1) - total_ranks
        if leftover and self.rank == 0:
            args = (self.cpus_per_worker, self.size - 1, leftover)
            self.logger.warning(
                "with `cpus_per_worker` = %d and %d available ranks, %d ranks will do no work"
                % args)

        # crash if we only have one process or one worker
        if self.size <= self.workers:
            args = (self.size, self.workers + 1, self.workers)
            raise ValueError(
                "only have %d ranks; need at least %d to use the desired %d workers"
                % args)

        # ranks that will do work have a nonzero color now
        self._valid_worker = color > 0

        # split the comm between the workers
        self.subcomm = self.comm.Split(color, 0)

        # set the global extension point comm
        GlobalComm.set(self.subcomm)
Exemplo n.º 2
0
 def _create_subcomm(self):
     """
     Internal function to create the sub-communicator that will be 
     used by each independent worker when running the task function
     
     Notes
     -----
     This function updates the global ``nbodykit`` communicator
     via ``set_nbkit_comm`` so all plugins will be initialized 
     with this sub-communicator
     """
     self.subcomm = None
     chain_ranks = []
     color = 0
     total_ranks = 0
     
     # split the ranks
     for i, ranks in split_ranks(self.size, self.cpus_per_worker, include_all=self.use_all_cpus):
         chain_ranks.append(ranks[0])
         if self.rank in ranks: color = i+1
         total_ranks += len(ranks)
     
     self.workers = i+1 # store the total number of workers
     leftover = (self.size - 1) - total_ranks
     if leftover and self.rank == 0:
         args = (self.cpus_per_worker, self.size-1, leftover)
         self.logger.warning("with `cpus_per_worker` = %d and %d available ranks, %d ranks will do no work" %args)
         
     # crash if we only have one process or one worker
     if self.size <= self.workers:
         args = (self.size, self.workers+1, self.workers)
         raise ValueError("only have %d ranks; need at least %d to use the desired %d workers" %args)
         
     # ranks that will do work have a nonzero color now
     self._valid_worker = color > 0
     
     # split the comm between the workers
     self.subcomm = self.comm.Split(color, 0)
     
     # set the global extension point comm
     GlobalComm.set(self.subcomm)
Exemplo n.º 3
0
 def wrapper(self, *args, **kwargs):
                     
     from nbodykit import GlobalComm
     setattr(self, 'comm', kwargs.pop('comm',  GlobalComm.get()))
     return init(self, *args, **kwargs)