lightning/tests/tests_pytorch/strategies/test_xla.py

71 lines
2.8 KiB
Python

# Copyright The Lightning AI 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 os
from unittest import mock
from unittest.mock import Mock
import torch
from lightning.fabric.accelerators.xla import _using_pjrt
from lightning.pytorch import Trainer
from lightning.pytorch.accelerators import XLAAccelerator
from lightning.pytorch.demos.boring_classes import BoringModel
from lightning.pytorch.strategies import XLAStrategy
from tests_pytorch.helpers.runif import RunIf
class BoringModelTPU(BoringModel):
def on_train_start(self) -> None:
index = 0 if _using_pjrt() else 1
# assert strategy attributes for device setting
assert self.device == torch.device("xla", index=index)
assert os.environ.get("PT_XLA_DEBUG") == "1"
@RunIf(tpu=True, standalone=True)
@mock.patch.dict(os.environ, os.environ.copy(), clear=True)
def test_xla_strategy_debug_state():
"""Tests if device/debug flag is set correctly when training and after teardown for XLAStrategy."""
model = BoringModelTPU()
trainer_kwargs = {}
if not _using_pjrt():
# only XRT supports XLA with a single process
trainer_kwargs["devices"] = 1
trainer = Trainer(fast_dev_run=True, strategy=XLAStrategy(debug=True), **trainer_kwargs)
assert isinstance(trainer.accelerator, XLAAccelerator)
assert isinstance(trainer.strategy, XLAStrategy)
trainer.fit(model)
assert "PT_XLA_DEBUG" not in os.environ
@mock.patch.dict(os.environ, os.environ.copy(), clear=True)
def test_rank_properties_access(xla_available):
"""Test that the strategy returns the expected values depending on whether we're in the main process or not."""
strategy = XLAStrategy()
strategy.cluster_environment = Mock()
# we're in the main process, no processes have been launched yet
assert not strategy._launched
assert strategy.global_rank == 0
assert strategy.local_rank == 0
assert strategy.node_rank == 0
assert strategy.world_size == 1
# simulate we're in a worker process
strategy._launched = True
assert strategy.global_rank == strategy.cluster_environment.global_rank()
assert strategy.local_rank == strategy.cluster_environment.local_rank()
assert strategy.node_rank == strategy.cluster_environment.node_rank()
assert strategy.world_size == strategy.cluster_environment.world_size()