lightning/pytorch_lightning/trainer/training_tricks.py

67 lines
2.2 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 abc import ABC, abstractmethod
import torch
from torch import Tensor
from pytorch_lightning import _logger as log
from pytorch_lightning.callbacks import GradientAccumulationScheduler
from pytorch_lightning.core.lightning import LightningModule
try:
from apex import amp
except ImportError:
amp = None
EPSILON = 1e-6
EPSILON_FP16 = 1e-5
class TrainerTrainingTricksMixin(ABC):
# this is just a summary on variables used in this abstract class,
# the proper values/initialisation should be done in child class
default_root_dir: str
progress_bar_callback: ...
on_gpu: bool
@abstractmethod
def get_model(self) -> LightningModule:
"""Warning: this is just empty shell for code implemented in other class."""
def print_nan_gradients(self) -> None:
model = self.get_model()
for param in model.parameters():
if (param.grad is not None) and torch.isnan(param.grad.float()).any():
log.info(param, param.grad)
def detect_nan_tensors(self, loss: Tensor) -> None:
model = self.get_model()
# check if loss is nan
if not torch.isfinite(loss).all():
raise ValueError(
'The loss returned in `training_step` is nan or inf.'
)
# check if a network weight is nan
for name, param in model.named_parameters():
if not torch.isfinite(param).all():
self.print_nan_gradients()
raise ValueError(
f'Detected nan and/or inf values in `{name}`.'
' Check your forward pass for numerically unstable operations.'
)