lightning/pytorch_lightning/accelerators/cpu_accelerator.py

91 lines
2.8 KiB
Python

# Copyright The PyTorch Lightning team.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
from typing import Any, Optional, Union, Callable
import torch
from pytorch_lightning.accelerators.accelerator import Accelerator, ReduceOp
from pytorch_lightning.cluster_environments import ClusterEnvironment
from pytorch_lightning.utilities import AMPType
from pytorch_lightning.utilities.exceptions import MisconfigurationException
class CPUAccelerator(Accelerator):
def __init__(self, trainer, cluster_environment: Optional[ClusterEnvironment] = None):
"""
Runs training on CPU
Example::
# default
trainer = Trainer(accelerator=CPUAccelerator())
"""
super().__init__(trainer, cluster_environment)
self.nickname = None
def setup(self, model):
# run through amp wrapper
if self.trainer.amp_backend:
raise MisconfigurationException('amp + cpu is not supported. Please use a GPU option')
# call setup after the ddp process has connected
self.trainer.call_setup_hook(model)
# CHOOSE OPTIMIZER
# allow for lr schedulers as well
self.setup_optimizers(model)
self.trainer.convert_to_lightning_optimizers()
self.trainer.model = model
def train(self):
model = self.trainer.model
# set up training routine
self.trainer.train_loop.setup_training(model)
# train or test
results = self.train_or_test()
return results
def _step(self, model_step: Callable, args):
if self.trainer.amp_backend == AMPType.NATIVE:
with torch.cuda.amp.autocast():
output = model_step(*args)
else:
output = model_step(*args)
return output
def training_step(self, args):
return self._step(self.trainer.model.training_step, args)
def validation_step(self, args):
return self._step(self.trainer.model.validation_step, args)
def test_step(self, args):
return self._step(self.trainer.model.test_step, args)
def sync_tensor(self,
tensor: Union[torch.Tensor],
group: Optional[Any] = None,
reduce_op: Optional[Union[ReduceOp, str]] = None) -> torch.Tensor:
return tensor
@property
def require_distributed_sampler(self):
return False