lightning/tests/trainer/test_trainer_tricks.py

159 lines
6.5 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 torch.utils.data import DataLoader, RandomSampler, SequentialSampler
from pytorch_lightning import Trainer
from tests.base import EvalModelTemplate
def test_num_training_batches(tmpdir):
"""
Tests that the correct number of batches are allocated
"""
# when we have fewer batches in the dataloader we should use those instead of the limit
model = EvalModelTemplate()
trainer = Trainer(
limit_val_batches=100,
limit_train_batches=100,
max_epochs=1,
default_root_dir=tmpdir,
)
trainer.fit(model)
assert len(model.train_dataloader()) == 10
assert len(model.val_dataloader()) == 10
assert isinstance(trainer.num_val_batches, list)
assert trainer.num_val_batches[0] == 10
assert trainer.num_training_batches == 10
# when we have more batches in the dataloader we should limit them
model = EvalModelTemplate()
trainer = Trainer(
limit_val_batches=7,
limit_train_batches=7,
max_epochs=1,
default_root_dir=tmpdir,
)
trainer.fit(model)
assert len(model.train_dataloader()) == 10
assert len(model.val_dataloader()) == 10
assert isinstance(trainer.num_val_batches, list)
assert trainer.num_val_batches[0] == 7
assert trainer.num_training_batches == 7
def test_overfit_batch_limits(tmpdir):
# ------------------------------------------------------
# Make sure shuffle is correct across loaders initially
# ------------------------------------------------------
model = EvalModelTemplate()
model.train_dataloader()
# original train loader which should be replaced in all methods
train_loader = model.train_dataloader()
# make sure the val and tests are not shuffled
assert isinstance(train_loader.sampler, RandomSampler)
assert isinstance(model.val_dataloader().sampler, SequentialSampler)
assert isinstance(model.test_dataloader().sampler, SequentialSampler)
# ------------------------------------------------------
# get the training loader and batch
# ------------------------------------------------------
# Create a reference train dataloader without shuffling.
train_loader = DataLoader(model.train_dataloader().dataset, shuffle=False)
(xa, ya) = next(iter(train_loader))
train_loader = DataLoader(model.train_dataloader().dataset, shuffle=True)
full_train_samples = len(train_loader)
num_train_samples = int(0.11 * full_train_samples)
# ------------------------------------------------------
# set VAL and Test loaders
# ------------------------------------------------------
val_loader = DataLoader(model.val_dataloader().dataset, shuffle=False)
test_loader = DataLoader(model.test_dataloader().dataset, shuffle=False)
# set the model loaders
model.train_dataloader = lambda: train_loader
model.val_dataloader = lambda: val_loader
model.test_dataloader = lambda: test_loader
# ------------------------------------------------------
# test train loader applies correct limits
# ------------------------------------------------------
trainer = Trainer(overfit_batches=4)
trainer.reset_train_dataloader(model)
assert trainer.num_training_batches == 4
# make sure the loaders are the same
(xb, yb) = next(iter(trainer.train_dataloader))
assert torch.eq(xa, xb).all()
assert torch.eq(ya, yb).all()
trainer = Trainer(overfit_batches=0.11)
trainer.reset_train_dataloader(model)
# The dataloader should have been overwritten with a Sequential sampler.
assert trainer.train_dataloader is not train_loader
assert trainer.num_training_batches == num_train_samples
# make sure the loaders are the same
(xb, yb) = next(iter(trainer.train_dataloader))
assert torch.eq(xa, xb).all()
assert torch.eq(ya, yb).all()
# ------------------------------------------------------
# run tests for both val and test
# ------------------------------------------------------
for split in ['val', 'test']:
# ------------------------------------------------------
# test overfit_batches as percent
# ------------------------------------------------------
loader_num_batches, dataloaders = Trainer(overfit_batches=0.11)._reset_eval_dataloader(model, split)
assert loader_num_batches[0] == num_train_samples
# make sure we turned off shuffle for the user
assert isinstance(dataloaders[0].sampler, SequentialSampler)
# make sure the loaders are the same
(xb, yb) = next(iter(dataloaders[0]))
assert torch.eq(xa, xb).all()
assert torch.eq(ya, yb).all()
# ------------------------------------------------------
# test overfit_batches as int
# ------------------------------------------------------
loader_num_batches, dataloaders = Trainer(overfit_batches=1)._reset_eval_dataloader(model, split)
assert loader_num_batches[0] == 1
loader_num_batches, dataloaders = Trainer(overfit_batches=5)._reset_eval_dataloader(model, split)
assert loader_num_batches[0] == 5
# ------------------------------------------------------
# test limit_xxx_batches as percent AND int
# ------------------------------------------------------
if split == 'val':
loader_num_batches, dataloaders = Trainer(limit_val_batches=0.1)._reset_eval_dataloader(model, split)
assert loader_num_batches[0] == int(0.1 * len(val_loader))
loader_num_batches, dataloaders = Trainer(limit_val_batches=10)._reset_eval_dataloader(model, split)
assert loader_num_batches[0] == 10
else:
loader_num_batches, dataloaders = Trainer(limit_test_batches=0.1)._reset_eval_dataloader(model, split)
assert loader_num_batches[0] == int(0.1 * len(test_loader))
loader_num_batches, dataloaders = Trainer(limit_test_batches=10)._reset_eval_dataloader(model, split)
assert loader_num_batches[0] == 10