lightning/pytorch_lightning/trainer/evaluation_loop.py

349 lines
13 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.
import torch
from pytorch_lightning.core.step_result import Result
from pytorch_lightning.trainer.supporters import PredictionCollection
from pytorch_lightning.utilities.apply_func import apply_to_collection
from pytorch_lightning.utilities.model_helpers import is_overridden
from pytorch_lightning.utilities.warnings import WarningCache
class EvaluationLoop(object):
def __init__(self, trainer):
self.trainer = trainer
self.outputs = []
self.step_metrics = []
self.predictions = None
self.max_batches = None
self.warning_cache = WarningCache()
self.num_dataloaders = None
def on_trainer_init(self):
self.trainer.num_val_batches = []
self.trainer.num_sanity_val_batches = []
self.trainer.num_test_batches = []
self.trainer.test_dataloaders = None
self.trainer.val_dataloaders = None
self.trainer.running_sanity_check = False
# when .test() is called, it sets this
self.trainer.tested_ckpt_path = None
# when true, prints test results
self.trainer.verbose_test = True
def get_evaluation_dataloaders(self, max_batches):
# select dataloaders
model = self.trainer.lightning_module
# select dataloaders
if self.trainer.testing:
self.trainer.reset_test_dataloader(model)
dataloaders = self.trainer.test_dataloaders
new_max_batches = self.trainer.num_test_batches
else:
# val
in_sanity_check = self.trainer.running_sanity_check
should_reload_every_epoch = self.trainer.reload_dataloaders_every_epoch
if (self.trainer.val_dataloaders is None or should_reload_every_epoch) and not in_sanity_check:
self.trainer.reset_val_dataloader(model)
dataloaders = self.trainer.val_dataloaders
new_max_batches = self.trainer.num_val_batches
if max_batches is None:
max_batches = new_max_batches
return dataloaders, max_batches
def should_skip_evaluation(self, max_batches):
return sum(max_batches) == 0
def on_evaluation_start(self, *args, **kwargs):
if self.trainer.testing:
self.trainer.call_hook('on_test_start', *args, **kwargs)
else:
self.trainer.call_hook('on_validation_start', *args, **kwargs)
def on_evaluation_model_eval(self, *_, **__):
model_ref = self.trainer.lightning_module
if self.trainer.testing:
model_ref.on_test_model_eval()
else:
model_ref.on_validation_model_eval()
def on_evaluation_model_train(self, *_, **__):
model_ref = self.trainer.lightning_module
if self.trainer.testing:
model_ref.on_test_model_train()
else:
model_ref.on_validation_model_train()
def on_evaluation_end(self, *args, **kwargs):
if self.trainer.testing:
self.trainer.call_hook('on_test_end', *args, **kwargs)
else:
self.trainer.call_hook('on_validation_end', *args, **kwargs)
def reload_evaluation_dataloaders(self):
model = self.trainer.lightning_module
if self.trainer.testing:
self.trainer.reset_test_dataloader(model)
else:
self.trainer.reset_val_dataloader(model)
def setup(self, model, max_batches, dataloaders):
# bookkeeping
self.outputs = []
self.predictions = PredictionCollection(self.trainer.global_rank, self.trainer.world_size)
# convert max_batches to list
if isinstance(max_batches, int):
max_batches = [max_batches] * len(dataloaders)
self.max_batches = max_batches
self.num_dataloaders = self._get_num_dataloaders(dataloaders)
self._predictions = [[] for _ in range(self.num_dataloaders)]
def on_evaluation_epoch_start(self, *args, **kwargs):
if self.trainer.testing:
self.trainer.call_hook('on_test_epoch_start', *args, **kwargs)
else:
self.trainer.call_hook('on_validation_epoch_start', *args, **kwargs)
def _build_args(self, batch, batch_idx, dataloader_idx):
# make dataloader_idx arg in validation_step optional
args = [batch, batch_idx]
multiple_val_loaders = (
not self.trainer.testing and self._get_num_dataloaders(self.trainer.val_dataloaders) > 1
)
multiple_test_loaders = (self.trainer.testing and self._get_num_dataloaders(self.trainer.test_dataloaders) > 1)
if multiple_test_loaders or multiple_val_loaders:
args.append(dataloader_idx)
return args
def _get_num_dataloaders(self, dataloaders):
# case where user does:
# return dl1, dl2
length = len(dataloaders)
if len(dataloaders) > 0 and isinstance(dataloaders[0], (list, tuple)):
length = len(dataloaders[0])
return length
def evaluation_step(self, batch, batch_idx, dataloader_idx):
# configure args
args = self._build_args(batch, batch_idx, dataloader_idx)
model_ref = self.trainer.lightning_module
model_ref._results = Result()
if self.testing:
model_ref._current_fx_name = "test_step"
with self.trainer.profiler.profile("test_step"):
output = self.trainer.accelerator.test_step(args)
else:
model_ref._current_fx_name = "validation_step"
with self.trainer.profiler.profile("validation_step"):
output = self.trainer.accelerator.validation_step(args)
# capture any logged information
self.trainer.logger_connector.cache_logged_metrics()
# track batch size for weighted average
is_result_obj = isinstance(output, Result)
if is_result_obj:
output.track_batch_size(batch)
return output
def evaluation_step_end(self, *args, **kwargs):
if self.trainer.testing:
output = self.trainer.call_hook('test_step_end', *args, **kwargs)
else:
output = self.trainer.call_hook('validation_step_end', *args, **kwargs)
return output
def evaluation_epoch_end(self):
# unset dataloder_idx in model
self.trainer.logger_connector.evaluation_epoch_end(self.trainer.testing)
# call the model epoch end
deprecated_results = self.__run_eval_epoch_end(self.num_dataloaders)
# enable returning anything
for i, r in enumerate(deprecated_results):
if not isinstance(r, (dict, Result, torch.Tensor)):
deprecated_results[i] = []
return deprecated_results
def log_epoch_metrics_on_evaluation_end(self):
# get the final loop results
eval_loop_results = self.trainer.logger_connector.get_evaluate_epoch_results()
return eval_loop_results
def __run_eval_epoch_end(self, num_dataloaders):
model = self.trainer.lightning_module
# with a single dataloader don't pass an array
outputs = self.outputs
eval_results = outputs
if num_dataloaders == 1:
eval_results = outputs[0]
user_reduced = False
if self.trainer.testing:
if is_overridden('test_epoch_end', model=model):
model._current_fx_name = 'test_epoch_end'
eval_results = model.test_epoch_end(eval_results)
user_reduced = True
else:
if is_overridden('validation_epoch_end', model=model):
model._current_fx_name = 'validation_epoch_end'
eval_results = model.validation_epoch_end(eval_results)
user_reduced = True
# capture logging
self.trainer.logger_connector.cache_logged_metrics()
# depre warning
if eval_results is not None and user_reduced:
step = 'testing_epoch_end' if self.trainer.testing else 'validation_epoch_end'
self.warning_cache.warn(
f'The {step} should not return anything as of 9.1.'
' To log, use self.log(...) or self.write(...) directly in the LightningModule'
)
if not isinstance(eval_results, list):
eval_results = [eval_results]
# track depreceated metrics
self.trainer.logger_connector.track_metrics_deprecated(eval_results)
return eval_results
def __gather_epoch_end_eval_results(self, outputs):
eval_results = []
for epoch_output in outputs:
result = epoch_output[0].__class__.gather(epoch_output)
if 'checkpoint_on' in result:
result.checkpoint_on = result.checkpoint_on.mean()
if 'early_stop_on' in result:
result.early_stop_on = result.early_stop_on.mean()
eval_results.append(result)
# with 1 dataloader don't pass in a list
if len(eval_results) == 1:
eval_results = eval_results[0]
return eval_results
def __auto_reduce_result_objs(self, outputs):
# outputs has a list of results per dataloader
eval_results = []
for dl_output in outputs:
result = dl_output[0]
result = result.__class__.reduce_on_epoch_end(dl_output)
if 'checkpoint_on' in result:
result.checkpoint_on = result.checkpoint_on.mean()
if 'early_stop_on' in result:
result.early_stop_on = result.early_stop_on.mean()
eval_results.append(result)
return eval_results
def on_predict_epoch_end(self):
self.trainer._progress_bar_callback.on_test_end(self.trainer, self.trainer.lightning_module)
results = self._predictions
def _convert_to_numpy(v):
return v.cpu().numpy()
results = apply_to_collection(results, torch.Tensor, _convert_to_numpy)
return results, None
def on_evaluation_batch_start(self, batch, batch_idx, dataloader_idx):
# set dataloader_idx to model and track batch_size
self.trainer.logger_connector.on_evaluation_batch_start(
self.trainer.testing, batch, dataloader_idx, self.num_dataloaders
)
if self.trainer.testing:
self.trainer.call_hook('on_test_batch_start', batch, batch_idx, dataloader_idx)
else:
self.trainer.call_hook('on_validation_batch_start', batch, batch_idx, dataloader_idx)
def on_evaluation_batch_end(self, output, batch, batch_idx, dataloader_idx):
if self.trainer.testing:
self.trainer.call_hook('on_test_batch_end', output, batch, batch_idx, dataloader_idx)
else:
self.trainer.call_hook('on_validation_batch_end', output, batch, batch_idx, dataloader_idx)
# store predicitons if do_write_predictions and track eval loss history
self.store_predictions(output, batch_idx, dataloader_idx)
def store_predictions(self, output, batch_idx, dataloader_idx):
# Add step predictions to prediction collection to write later
if output is not None:
do_write_predictions = isinstance(output, Result) and self.trainer.testing
if do_write_predictions:
self.predictions.add(output.pop('predictions', None))
# track debug metrics
self.trainer.dev_debugger.track_eval_loss_history(batch_idx, dataloader_idx, output)
def on_evaluation_epoch_end(self, *args, **kwargs):
# call the callback hook
if self.trainer.testing:
self.trainer.call_hook('on_test_epoch_end', *args, **kwargs)
else:
self.trainer.call_hook('on_validation_epoch_end', *args, **kwargs)
self.trainer.call_hook('on_epoch_end')
def log_evaluation_step_metrics(self, output, batch_idx):
if self.trainer.running_sanity_check:
return
step_log_metrics = {}
step_pbar_metrics = {}
self.__log_result_step_metrics(step_log_metrics, step_pbar_metrics, batch_idx)
def __log_result_step_metrics(self, step_log_metrics, step_pbar_metrics, batch_idx):
cached_results = self.trainer.logger_connector.cached_results
cached_batch_pbar_metrics, cached_batch_log_metrics = cached_results.update_logger_connector()
step_log_metrics.update(cached_batch_log_metrics)
step_pbar_metrics.update(cached_batch_pbar_metrics)
if len(step_log_metrics) > 0:
# make the metrics appear as a different line in the same graph
metrics_by_epoch = {}
for k, v in step_log_metrics.items():
metrics_by_epoch[f'{k}/epoch_{self.trainer.current_epoch}'] = v
self.trainer.logger_connector.log_metrics(metrics_by_epoch, {}, step=batch_idx)
if len(step_pbar_metrics) > 0:
self.trainer.logger_connector.add_progress_bar_metrics(step_pbar_metrics)