lightning/tests/trainer/test_trainer.py

627 lines
19 KiB
Python

import glob
import math
import os
from argparse import Namespace
import pytest
import torch
import tests.base.utils as tutils
from pytorch_lightning import Trainer
from pytorch_lightning.callbacks import (
EarlyStopping,
ModelCheckpoint,
)
from pytorch_lightning.core.lightning import load_hparams_from_tags_csv
from pytorch_lightning.trainer.logging import TrainerLoggingMixin
from pytorch_lightning.utilities.debugging import MisconfigurationException
from tests.base import (
TestModelBase,
DictHparamsModel,
LightningTestModel,
LightEmptyTestStep,
LightValidationStepMixin,
LightValidationMultipleDataloadersMixin,
LightTrainDataloader,
LightTestDataloader,
)
def test_hparams_save_load(tmpdir):
model = DictHparamsModel({'in_features': 28 * 28, 'out_features': 10})
# logger file to get meta
trainer_options = dict(
default_save_path=tmpdir,
max_epochs=2,
)
# fit model
trainer = Trainer(**trainer_options)
result = trainer.fit(model)
assert result == 1
# try to load the model now
pretrained_model = tutils.load_model_from_checkpoint(
trainer.checkpoint_callback.dirpath,
module_class=DictHparamsModel
)
def test_no_val_module(tmpdir):
"""Tests use case where trainer saves the model, and user loads it from tags independently."""
tutils.reset_seed()
hparams = tutils.get_default_hparams()
class CurrentTestModel(LightTrainDataloader, TestModelBase):
pass
model = CurrentTestModel(hparams)
# logger file to get meta
logger = tutils.get_default_testtube_logger(tmpdir, False)
trainer_options = dict(
max_epochs=1,
logger=logger,
checkpoint_callback=ModelCheckpoint(tmpdir)
)
# fit model
trainer = Trainer(**trainer_options)
result = trainer.fit(model)
# training complete
assert result == 1, 'amp + ddp model failed to complete'
# save model
new_weights_path = os.path.join(tmpdir, 'save_test.ckpt')
trainer.save_checkpoint(new_weights_path)
# load new model
tags_path = tutils.get_data_path(logger, path_dir=tmpdir)
tags_path = os.path.join(tags_path, 'meta_tags.csv')
model_2 = LightningTestModel.load_from_checkpoint(
checkpoint_path=new_weights_path,
tags_csv=tags_path
)
model_2.eval()
def test_no_val_end_module(tmpdir):
"""Tests use case where trainer saves the model, and user loads it from tags independently."""
tutils.reset_seed()
class CurrentTestModel(LightTrainDataloader, LightValidationStepMixin, TestModelBase):
pass
hparams = tutils.get_default_hparams()
model = CurrentTestModel(hparams)
# logger file to get meta
logger = tutils.get_default_testtube_logger(tmpdir, False)
trainer_options = dict(
max_epochs=1,
logger=logger,
checkpoint_callback=ModelCheckpoint(tmpdir)
)
# fit model
trainer = Trainer(**trainer_options)
result = trainer.fit(model)
# traning complete
assert result == 1, 'amp + ddp model failed to complete'
# save model
new_weights_path = os.path.join(tmpdir, 'save_test.ckpt')
trainer.save_checkpoint(new_weights_path)
# load new model
tags_path = tutils.get_data_path(logger, path_dir=tmpdir)
tags_path = os.path.join(tags_path, 'meta_tags.csv')
model_2 = LightningTestModel.load_from_checkpoint(
checkpoint_path=new_weights_path,
tags_csv=tags_path
)
model_2.eval()
def test_gradient_accumulation_scheduling(tmpdir):
"""
Test grad accumulation by the freq of optimizer updates
"""
tutils.reset_seed()
# test incorrect configs
with pytest.raises(IndexError):
assert Trainer(accumulate_grad_batches={0: 3, 1: 4, 4: 6})
assert Trainer(accumulate_grad_batches={-2: 3})
with pytest.raises(TypeError):
assert Trainer(accumulate_grad_batches={})
assert Trainer(accumulate_grad_batches=[[2, 3], [4, 6]])
assert Trainer(accumulate_grad_batches={1: 2, 3.: 4})
assert Trainer(accumulate_grad_batches={1: 2.5, 3: 5})
# test optimizer call freq matches scheduler
def _optimizer_step(self, epoch, batch_idx, optimizer,
optimizer_idx, second_order_closure=None):
# only test the first 12 batches in epoch
if batch_idx < 12:
if epoch == 0:
# reset counter when starting epoch
if batch_idx == 0:
self.prev_called_batch_idx = 0
# use this opportunity to test once
assert self.trainer.accumulate_grad_batches == 1
assert batch_idx == self.prev_called_batch_idx
self.prev_called_batch_idx += 1
elif 1 <= epoch <= 2:
# reset counter when starting epoch
if batch_idx == 1:
self.prev_called_batch_idx = 1
# use this opportunity to test once
assert self.trainer.accumulate_grad_batches == 2
assert batch_idx == self.prev_called_batch_idx
self.prev_called_batch_idx += 2
else:
if batch_idx == 3:
self.prev_called_batch_idx = 3
# use this opportunity to test once
assert self.trainer.accumulate_grad_batches == 4
assert batch_idx == self.prev_called_batch_idx
self.prev_called_batch_idx += 3
optimizer.step()
# clear gradients
optimizer.zero_grad()
hparams = tutils.get_default_hparams()
model = LightningTestModel(hparams)
schedule = {1: 2, 3: 4}
trainer = Trainer(accumulate_grad_batches=schedule,
train_percent_check=0.1,
val_percent_check=0.1,
max_epochs=4,
default_save_path=tmpdir)
# for the test
trainer.optimizer_step = _optimizer_step
model.prev_called_batch_idx = 0
trainer.fit(model)
def test_loading_meta_tags(tmpdir):
tutils.reset_seed()
hparams = tutils.get_default_hparams()
# save tags
logger = tutils.get_default_testtube_logger(tmpdir, False)
logger.log_hyperparams(Namespace(some_str='a_str', an_int=1, a_float=2.0))
logger.log_hyperparams(hparams)
logger.save()
# load tags
path_expt_dir = tutils.get_data_path(logger, path_dir=tmpdir)
tags_path = os.path.join(path_expt_dir, 'meta_tags.csv')
tags = load_hparams_from_tags_csv(tags_path)
assert tags.batch_size == 32 and tags.hidden_dim == 1000
def test_dp_output_reduce():
mixin = TrainerLoggingMixin()
tutils.reset_seed()
# test identity when we have a single gpu
out = torch.rand(3, 1)
assert mixin.reduce_distributed_output(out, num_gpus=1) is out
# average when we have multiples
assert mixin.reduce_distributed_output(out, num_gpus=2) == out.mean()
# when we have a dict of vals
out = {
'a': out,
'b': {
'c': out
}
}
reduced = mixin.reduce_distributed_output(out, num_gpus=3)
assert reduced['a'] == out['a']
assert reduced['b']['c'] == out['b']['c']
def test_model_checkpoint_options(tmpdir):
"""Test ModelCheckpoint options."""
def mock_save_function(filepath):
open(filepath, 'a').close()
hparams = tutils.get_default_hparams()
_ = LightningTestModel(hparams)
# simulated losses
save_dir = os.path.join(tmpdir, '1')
os.mkdir(save_dir)
losses = [10, 9, 2.8, 5, 2.5]
# -----------------
# CASE K=-1 (all)
checkpoint_callback = ModelCheckpoint(save_dir, save_top_k=-1, verbose=1)
checkpoint_callback.save_function = mock_save_function
trainer = Trainer()
# emulate callback's calls during the training
for i, loss in enumerate(losses):
trainer.current_epoch = i
trainer.callback_metrics = {'val_loss': loss}
checkpoint_callback.on_validation_end(trainer, trainer.get_model())
file_lists = set(os.listdir(save_dir))
assert len(file_lists) == len(losses), "Should save all models when save_top_k=-1"
# verify correct naming
for fname in {'epoch=4.ckpt',
'epoch=3.ckpt',
'epoch=2.ckpt',
'epoch=1.ckpt',
'epoch=0.ckpt'}:
assert fname in file_lists
save_dir = os.path.join(tmpdir, '2')
os.mkdir(save_dir)
# -----------------
# CASE K=0 (none)
checkpoint_callback = ModelCheckpoint(save_dir, save_top_k=0, verbose=1)
checkpoint_callback.save_function = mock_save_function
trainer = Trainer()
# emulate callback's calls during the training
for i, loss in enumerate(losses):
trainer.current_epoch = i
trainer.callback_metrics = {'val_loss': loss}
checkpoint_callback.on_validation_end(trainer, trainer.get_model())
file_lists = os.listdir(save_dir)
assert len(file_lists) == 0, "Should save 0 models when save_top_k=0"
save_dir = os.path.join(tmpdir, '3')
os.mkdir(save_dir)
# -----------------
# CASE K=1 (2.5, epoch 4)
checkpoint_callback = ModelCheckpoint(save_dir, save_top_k=1, verbose=1, prefix='test_prefix_')
checkpoint_callback.save_function = mock_save_function
trainer = Trainer()
# emulate callback's calls during the training
for i, loss in enumerate(losses):
trainer.current_epoch = i
trainer.callback_metrics = {'val_loss': loss}
checkpoint_callback.on_validation_end(trainer, trainer.get_model())
file_lists = set(os.listdir(save_dir))
assert len(file_lists) == 1, "Should save 1 model when save_top_k=1"
assert 'test_prefix_epoch=4.ckpt' in file_lists
save_dir = os.path.join(tmpdir, '4')
os.mkdir(save_dir)
# -----------------
# CASE K=2 (2.5 epoch 4, 2.8 epoch 2)
# make sure other files don't get deleted
checkpoint_callback = ModelCheckpoint(save_dir, save_top_k=2, verbose=1)
open(f"{save_dir}/other_file.ckpt", 'a').close()
checkpoint_callback.save_function = mock_save_function
trainer = Trainer()
# emulate callback's calls during the training
for i, loss in enumerate(losses):
trainer.current_epoch = i
trainer.callback_metrics = {'val_loss': loss}
checkpoint_callback.on_validation_end(trainer, trainer.get_model())
file_lists = set(os.listdir(save_dir))
assert len(file_lists) == 3, 'Should save 2 model when save_top_k=2'
for fname in {'epoch=4.ckpt',
'epoch=2.ckpt',
'other_file.ckpt'}:
assert fname in file_lists
save_dir = os.path.join(tmpdir, '5')
os.mkdir(save_dir)
# -----------------
# CASE K=4 (save all 4 base)
# multiple checkpoints within same epoch
checkpoint_callback = ModelCheckpoint(save_dir, save_top_k=4, verbose=1)
checkpoint_callback.save_function = mock_save_function
trainer = Trainer()
# emulate callback's calls during the training
for loss in losses:
trainer.current_epoch = 0
trainer.callback_metrics = {'val_loss': loss}
checkpoint_callback.on_validation_end(trainer, trainer.get_model())
file_lists = set(os.listdir(save_dir))
assert len(file_lists) == 4, 'Should save all 4 models when save_top_k=4 within same epoch'
save_dir = os.path.join(tmpdir, '6')
os.mkdir(save_dir)
# -----------------
# CASE K=3 (save the 2nd, 3rd, 4th model)
# multiple checkpoints within same epoch
checkpoint_callback = ModelCheckpoint(save_dir, save_top_k=3, verbose=1)
checkpoint_callback.save_function = mock_save_function
trainer = Trainer()
# emulate callback's calls during the training
for loss in losses:
trainer.current_epoch = 0
trainer.callback_metrics = {'val_loss': loss}
checkpoint_callback.on_validation_end(trainer, trainer.get_model())
file_lists = set(os.listdir(save_dir))
assert len(file_lists) == 3, 'Should save 3 models when save_top_k=3'
for fname in {'epoch=0.ckpt',
'epoch=0.ckpt',
'epoch=0.ckpt'}:
assert fname in file_lists
def test_model_freeze_unfreeze():
tutils.reset_seed()
hparams = tutils.get_default_hparams()
model = LightningTestModel(hparams)
model.freeze()
model.unfreeze()
def test_resume_from_checkpoint_epoch_restored(tmpdir):
"""Verify resuming from checkpoint runs the right number of epochs"""
import types
tutils.reset_seed()
hparams = tutils.get_default_hparams()
def _new_model():
# Create a model that tracks epochs and batches seen
model = LightningTestModel(hparams)
model.num_epochs_seen = 0
model.num_batches_seen = 0
def increment_epoch(self):
self.num_epochs_seen += 1
def increment_batch(self, _):
self.num_batches_seen += 1
# Bind the increment_epoch function on_epoch_end so that the
# model keeps track of the number of epochs it has seen.
model.on_epoch_end = types.MethodType(increment_epoch, model)
model.on_batch_start = types.MethodType(increment_batch, model)
return model
model = _new_model()
trainer_options = dict(
show_progress_bar=False,
max_epochs=2,
train_percent_check=0.65,
val_percent_check=1,
checkpoint_callback=ModelCheckpoint(tmpdir, save_top_k=-1),
logger=False,
default_save_path=tmpdir,
early_stop_callback=False,
val_check_interval=1.,
)
# fit model
trainer = Trainer(**trainer_options)
trainer.fit(model)
training_batches = trainer.num_training_batches
assert model.num_epochs_seen == 2
assert model.num_batches_seen == training_batches * 2
# Other checkpoints can be uncommented if/when resuming mid-epoch is supported
checkpoints = sorted(glob.glob(os.path.join(trainer.checkpoint_callback.dirpath, '*.ckpt')))
for check in checkpoints:
next_model = _new_model()
state = torch.load(check)
# Resume training
trainer_options['max_epochs'] = 4
new_trainer = Trainer(**trainer_options, resume_from_checkpoint=check)
new_trainer.fit(next_model)
assert state['global_step'] + next_model.num_batches_seen == training_batches * 4
def _init_steps_model():
"""private method for initializing a model with 5% train epochs"""
tutils.reset_seed()
model, _ = tutils.get_default_model()
# define train epoch to 5% of data
train_percent = 0.05
# get number of samples in 1 epoch
num_train_samples = math.floor(len(model.train_dataloader()) * train_percent)
trainer_options = dict(
train_percent_check=train_percent,
)
return model, trainer_options, num_train_samples
def test_trainer_max_steps_and_epochs(tmpdir):
"""Verify model trains according to specified max steps"""
model, trainer_options, num_train_samples = _init_steps_model()
# define less train steps than epochs
trainer_options.update(dict(
default_save_path=tmpdir,
max_epochs=5,
max_steps=num_train_samples + 10
))
# fit model
trainer = Trainer(**trainer_options)
result = trainer.fit(model)
assert result == 1, "Training did not complete"
# check training stopped at max_steps
assert trainer.global_step == trainer.max_steps, "Model did not stop at max_steps"
# define less train epochs than steps
trainer_options.update(dict(
max_epochs=2,
max_steps=trainer_options['max_epochs'] * 2 * num_train_samples
))
# fit model
trainer = Trainer(**trainer_options)
result = trainer.fit(model)
assert result == 1, "Training did not complete"
# check training stopped at max_epochs
assert trainer.global_step == num_train_samples * trainer.max_epochs \
and trainer.current_epoch == trainer.max_epochs - 1, "Model did not stop at max_epochs"
def test_trainer_min_steps_and_epochs(tmpdir):
"""Verify model trains according to specified min steps"""
model, trainer_options, num_train_samples = _init_steps_model()
# define callback for stopping the model and default epochs
trainer_options.update(dict(
default_save_path=tmpdir,
early_stop_callback=EarlyStopping(monitor='val_loss', min_delta=1.0),
val_check_interval=2,
min_epochs=1,
max_epochs=10
))
# define less min steps than 1 epoch
trainer_options['min_steps'] = math.floor(num_train_samples / 2)
# fit model
trainer = Trainer(**trainer_options)
result = trainer.fit(model)
assert result == 1, "Training did not complete"
# check model ran for at least min_epochs
assert trainer.global_step >= num_train_samples and \
trainer.current_epoch > 0, "Model did not train for at least min_epochs"
# define less epochs than min_steps
trainer_options['min_steps'] = math.floor(num_train_samples * 1.5)
# fit model
trainer = Trainer(**trainer_options)
result = trainer.fit(model)
assert result == 1, "Training did not complete"
# check model ran for at least num_train_samples*1.5
assert trainer.global_step >= math.floor(num_train_samples * 1.5) and \
trainer.current_epoch > 0, "Model did not train for at least min_steps"
def test_benchmark_option(tmpdir):
"""Verify benchmark option."""
tutils.reset_seed()
class CurrentTestModel(
LightValidationMultipleDataloadersMixin,
LightTrainDataloader,
TestModelBase
):
pass
hparams = tutils.get_default_hparams()
model = CurrentTestModel(hparams)
# verify torch.backends.cudnn.benchmark is not turned on
assert not torch.backends.cudnn.benchmark
# logger file to get meta
trainer_options = dict(
default_save_path=tmpdir,
max_epochs=1,
benchmark=True,
)
# fit model
trainer = Trainer(**trainer_options)
result = trainer.fit(model)
# verify training completed
assert result == 1
# verify torch.backends.cudnn.benchmark is not turned off
assert torch.backends.cudnn.benchmark
def test_testpass_overrides(tmpdir):
hparams = tutils.get_default_hparams()
class LocalModel(LightTrainDataloader, TestModelBase):
pass
class LocalModelNoEnd(LightTrainDataloader, LightTestDataloader, LightEmptyTestStep, TestModelBase):
pass
class LocalModelNoStep(LightTrainDataloader, TestModelBase):
def test_epoch_end(self, outputs):
return {}
# Misconfig when neither test_step or test_end is implemented
with pytest.raises(MisconfigurationException):
model = LocalModel(hparams)
Trainer().test(model)
# Misconfig when neither test_step or test_end is implemented
with pytest.raises(MisconfigurationException):
model = LocalModelNoStep(hparams)
Trainer().test(model)
# No exceptions when one or both of test_step or test_end are implemented
model = LocalModelNoEnd(hparams)
Trainer().test(model)
model = LightningTestModel(hparams)
Trainer().test(model)