lightning/tests/tests_fabric/strategies/test_dp.py

71 lines
2.7 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 unittest import mock
from unittest.mock import MagicMock, Mock
import torch
from lightning.fabric.strategies import DataParallelStrategy
def test_data_parallel_root_device():
strategy = DataParallelStrategy()
strategy.parallel_devices = [torch.device("cuda", 2), torch.device("cuda", 0), torch.device("cuda", 1)]
assert strategy.root_device == torch.device("cuda", 2)
def test_data_parallel_ranks():
strategy = DataParallelStrategy()
assert strategy.world_size == 1
assert strategy.local_rank == 0
assert strategy.global_rank == 0
assert strategy.is_global_zero
@mock.patch("lightning.fabric.strategies.dp.DataParallel")
def test_data_parallel_setup_module(data_parallel_mock):
strategy = DataParallelStrategy()
strategy.parallel_devices = [0, 2, 1]
module = torch.nn.Linear(2, 2)
wrapped_module = strategy.setup_module(module)
assert wrapped_module == data_parallel_mock(module=module, device_ids=[0, 2, 1])
def test_data_parallel_module_to_device():
strategy = DataParallelStrategy()
strategy.parallel_devices = [torch.device("cuda", 2)]
module = Mock()
strategy.module_to_device(module)
module.to.assert_called_with(torch.device("cuda", 2))
def test_dp_module_state_dict():
"""Test that the module state dict gets retrieved without the prefixed wrapper keys from DP."""
class DataParallelMock(MagicMock):
def __instancecheck__(self, instance):
# to make the strategy's `isinstance(model, DataParallel)` pass with a mock as class
return True
strategy = DataParallelStrategy(parallel_devices=[torch.device("cpu"), torch.device("cpu")])
# Without DP applied (no setup call)
original_module = torch.nn.Linear(2, 3)
assert strategy.get_module_state_dict(original_module).keys() == original_module.state_dict().keys()
# With DP applied (setup called)
with mock.patch("lightning.fabric.strategies.dp.DataParallel", DataParallelMock):
wrapped_module = strategy.setup_module(original_module)
assert strategy.get_module_state_dict(wrapped_module).keys() == original_module.state_dict().keys()