lightning/tests/accelerators/test_cpu.py

88 lines
3.6 KiB
Python

import os
from pathlib import Path
from typing import Any, Dict, Union
import pytest
import torch
from pytorch_lightning import Trainer
from pytorch_lightning.accelerators import CPUAccelerator
from pytorch_lightning.plugins import SingleDevicePlugin
from pytorch_lightning.plugins.io.torch_plugin import TorchCheckpointIO
from pytorch_lightning.plugins.precision.precision_plugin import PrecisionPlugin
from tests.helpers.boring_model import BoringModel
@pytest.mark.parametrize("delay_dispatch", [True, False])
def test_plugin_setup_optimizers_in_pre_dispatch(tmpdir, delay_dispatch):
"""Test when using a custom training type plugin that delays setup optimizers, we do not call setup optimizers
till ``pre_dispatch``."""
class TestModel(BoringModel):
def on_fit_start(self):
if delay_dispatch:
# Ensure we haven't setup optimizers if we've delayed dispatch
assert len(self.trainer.optimizers) == 0
else:
assert len(self.trainer.optimizers) > 0
def on_fit_end(self):
assert len(self.trainer.optimizers) > 0
class CustomPlugin(SingleDevicePlugin):
@property
def setup_optimizers_in_pre_dispatch(self) -> bool:
return delay_dispatch
model = TestModel()
trainer = Trainer(default_root_dir=tmpdir, fast_dev_run=True, strategy=CustomPlugin(device=torch.device("cpu")))
trainer.fit(model)
def test_restore_checkpoint_after_pre_dispatch_default():
"""Assert default for restore_checkpoint_after_pre_dispatch is False."""
plugin = SingleDevicePlugin(torch.device("cpu"))
accelerator = CPUAccelerator(training_type_plugin=plugin, precision_plugin=PrecisionPlugin())
assert not accelerator.training_type_plugin.restore_checkpoint_after_pre_dispatch
assert not plugin.restore_checkpoint_after_pre_dispatch
@pytest.mark.parametrize("restore_after_pre_dispatch", [True, False])
def test_restore_checkpoint_after_pre_dispatch(tmpdir, restore_after_pre_dispatch):
"""Test to ensure that if restore_checkpoint_after_pre_dispatch is True, then we only load the state after pre-
dispatch is called."""
class TestPlugin(SingleDevicePlugin):
predispatched_called = False
def pre_dispatch(self) -> None:
super().pre_dispatch()
self.predispatched_called = True
@property
def restore_checkpoint_after_pre_dispatch(self) -> bool:
return restore_after_pre_dispatch
def load_checkpoint(self, checkpoint_path: Union[str, Path]) -> Dict[str, Any]:
assert self.predispatched_called == restore_after_pre_dispatch
return super().load_checkpoint(checkpoint_path)
model = BoringModel()
trainer = Trainer(default_root_dir=tmpdir, fast_dev_run=True)
trainer.fit(model)
checkpoint_path = os.path.join(tmpdir, "model.pt")
trainer.save_checkpoint(checkpoint_path)
plugin = TestPlugin(torch.device("cpu"), checkpoint_io=TorchCheckpointIO())
accelerator = CPUAccelerator(training_type_plugin=plugin, precision_plugin=PrecisionPlugin())
assert accelerator.training_type_plugin.restore_checkpoint_after_pre_dispatch == restore_after_pre_dispatch
assert plugin.restore_checkpoint_after_pre_dispatch == restore_after_pre_dispatch
trainer = Trainer(default_root_dir=tmpdir, accelerator=accelerator, fast_dev_run=True)
trainer.fit(model, ckpt_path=checkpoint_path)
for func in (trainer.test, trainer.validate, trainer.predict):
accelerator.training_type_plugin.predispatched_called = False
func(model, ckpt_path=checkpoint_path)