lightning/tests/tests_data/cache/test_cache.py

206 lines
6.4 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
import sys
from functools import partial
import numpy as np
import pytest
import torch
from lightning import seed_everything
from lightning.data.cache import Cache
from lightning.data.cache.dataloader import LightningDataLoader
from lightning.data.datasets.env import _DistributedEnv
from lightning.fabric import Fabric
from lightning.pytorch.demos.boring_classes import RandomDataset
from lightning_utilities.core.imports import RequirementCache
from torch.utils.data import Dataset
_PIL_AVAILABLE = RequirementCache("PIL")
_TORCH_VISION_AVAILABLE = RequirementCache("torchvision")
class ImageDataset(Dataset):
def __init__(self, tmpdir, cache, size, num_classes):
from PIL import Image
self.data = []
self.cache = cache
seed_everything(42)
for i in range(size):
path = os.path.join(tmpdir, f"img{i}.jpeg")
np_data = np.random.randint(255, size=(28, 28), dtype=np.uint8)
img = Image.fromarray(np_data).convert("L")
img.save(path, format="jpeg", quality=100)
self.data.append({"image": path, "class": np.random.randint(num_classes)})
def __len__(self):
return len(self.data)
def __getitem__(self, index):
if self.cache.filled:
return self.cache[index]
self.cache[index] = {**self.data[index], "index": index}
return None
def _cache_for_image_dataset(num_workers, tmpdir, fabric=None):
from PIL import Image
from torchvision.transforms import PILToTensor
dataset_size = 85
cache_dir = os.path.join(tmpdir, "cache")
distributed_env = _DistributedEnv.detect()
cache = Cache(cache_dir, chunk_size=10)
dataset = ImageDataset(tmpdir, cache, dataset_size, 10)
dataloader = LightningDataLoader(dataset, num_workers=num_workers, batch_size=4)
for _ in dataloader:
pass
# Not strictly required but added to avoid race condition
if distributed_env.world_size > 1:
fabric.barrier()
assert cache.filled
for i in range(len(dataset)):
cached_data = dataset[i]
original_data = dataset.data[i]
assert cached_data["class"] == original_data["class"]
original_array = PILToTensor()(Image.open(original_data["image"]))
assert torch.equal(original_array, cached_data["image"])
if distributed_env.world_size == 1:
indexes = []
dataloader = LightningDataLoader(dataset, num_workers=num_workers, batch_size=4)
for batch in dataloader:
if batch:
indexes.extend(batch["index"].numpy().tolist())
assert len(indexes) == dataset_size
seed_everything(42)
dataloader = LightningDataLoader(dataset, num_workers=num_workers, batch_size=4, shuffle=True)
dataloader_iter = iter(dataloader)
indexes = []
for batch in dataloader_iter:
indexes.extend(batch["index"].numpy().tolist())
if distributed_env.world_size == 1:
assert len(indexes) == dataset_size
indexes2 = []
for batch in dataloader_iter:
indexes2.extend(batch["index"].numpy().tolist())
assert indexes2 != indexes
@pytest.mark.skipif(
condition=not _PIL_AVAILABLE or not _TORCH_VISION_AVAILABLE, reason="Requires: ['pil', 'torchvision']"
)
@pytest.mark.parametrize("num_workers", [0, 1, 2])
def test_cache_for_image_dataset(num_workers, tmpdir):
cache_dir = os.path.join(tmpdir, "cache")
os.makedirs(cache_dir)
_cache_for_image_dataset(num_workers, tmpdir)
def _fabric_cache_for_image_dataset(fabric, num_workers, tmpdir):
_cache_for_image_dataset(num_workers, tmpdir, fabric=fabric)
@pytest.mark.skipif(
condition=not _PIL_AVAILABLE or not _TORCH_VISION_AVAILABLE or sys.platform == "win32",
reason="Requires: ['pil', 'torchvision']",
)
@pytest.mark.parametrize("num_workers", [2])
def test_cache_for_image_dataset_distributed(num_workers, tmpdir):
cache_dir = os.path.join(tmpdir, "cache")
os.makedirs(cache_dir)
fabric = Fabric(accelerator="cpu", devices=2, strategy="ddp_spawn")
fabric.launch(partial(_fabric_cache_for_image_dataset, num_workers=num_workers, tmpdir=tmpdir))
def test_cache_with_simple_format(tmpdir):
cache_dir = os.path.join(tmpdir, "cache1")
os.makedirs(cache_dir)
cache = Cache(cache_dir, chunk_bytes=90)
for i in range(100):
cache[i] = i
cache.done()
cache.merge()
for i in range(100):
assert i == cache[i]
cache_dir = os.path.join(tmpdir, "cache2")
os.makedirs(cache_dir)
cache = Cache(cache_dir, chunk_bytes=90)
for i in range(100):
cache[i] = [i, {0: [i + 1]}]
cache.done()
cache.merge()
for i in range(100):
assert [i, {0: [i + 1]}] == cache[i]
def test_cache_with_auto_wrapping(tmpdir):
os.makedirs(os.path.join(tmpdir, "cache_1"), exist_ok=True)
dataset = RandomDataset(64, 64)
dataloader = LightningDataLoader(dataset, cache_dir=os.path.join(tmpdir, "cache_1"), chunk_bytes=2 << 12)
for batch in dataloader:
assert isinstance(batch, torch.Tensor)
assert sorted(os.listdir(os.path.join(tmpdir, "cache_1"))) == [
"chunk-0-0.bin",
"chunk-0-1.bin",
"chunk-0-2.bin",
"index.json",
]
# Your dataset is optimised for the cloud
class RandomDatasetAtRuntime(Dataset):
def __init__(self, size: int, length: int):
self.len = length
self.size = size
def __getitem__(self, index: int) -> torch.Tensor:
return torch.randn(1, self.size)
def __len__(self) -> int:
return self.len
os.makedirs(os.path.join(tmpdir, "cache_2"), exist_ok=True)
dataset = RandomDatasetAtRuntime(64, 64)
dataloader = LightningDataLoader(dataset, cache_dir=os.path.join(tmpdir, "cache_2"), chunk_bytes=2 << 12)
with pytest.raises(ValueError, match="Your dataset items aren't deterministic"):
for batch in dataloader:
pass