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)
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)
def wrapper(self, *args, **kwargs):
from nbodykit import GlobalComm
setattr(self, 'comm', kwargs.pop('comm', GlobalComm.get()))
return init(self, *args, **kwargs)
