Improve StreamingDataset Speed

[tchaton]

What does this PR do?

Using this script, we found the reader and prepare thread interraction could lead to hanging over the locks to up to 8 seconds. This PR moves away from locks and uses queue instead to avoid losing any time to synchornize download and deletion of chunks.

# Subclass and override the '__getitem__' to add any transforms
class ResizedStreamingDataset(StreamingDataset):

    def __getitem__(self, index):
        img = super().__getitem__(index)
        # Note: This could have been done during optimization 
        # for faster data loading
        if img.shape[0] == 1:
            img = img.repeat((3, 1, 1))
        if img.shape[0] == 4:
            img = img[:3]
        return F.resize(img, (224, 224), antialias=True)


# To be used once you have optimized the data with lightning.data.optimize
dataset = ResizedStreamingDataset(input_dir=input_dir)

# Works out of the box with PyTorch DataLoader
dataloader = DataLoader(dataset, batch_size=64, num_workers=os.cpu_count(), prefetch_factor=8)

# Iterate over the dataset once
for batch in dataloader:
    pass

# Iterate over the dataset twice
for batch in dataloader:
    pass

Fixes #<issue_number>

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📚 Documentation preview 📚: https://pytorch-lightning--19114.org.readthedocs.build/en/19114/

cc @Borda

[github-actions]

⚡ Required checks status: All passing 🟢

Groups summary

🟢 lightning_data: CPU workflow

Check ID	Status
data-cpu (macOS-11, lightning, 3.10, 2.1)	success	✅
data-cpu (ubuntu-20.04, lightning, 3.10, 2.1)	success	✅
data-cpu (windows-2022, lightning, 3.10, 2.1)	success	✅

These checks are required after the changes to src/lightning/data/streaming/reader.py, tests/tests_data/streaming/test_reader.py.

🟢 mypy

Check ID	Status
mypy	success	✅

These checks are required after the changes to src/lightning/data/streaming/reader.py.

🟢 install

Check ID	Status
install-pkg (ubuntu-22.04, app, 3.8)	success	✅
install-pkg (ubuntu-22.04, app, 3.11)	success	✅
install-pkg (ubuntu-22.04, fabric, 3.8)	success	✅
install-pkg (ubuntu-22.04, fabric, 3.11)	success	✅
install-pkg (ubuntu-22.04, pytorch, 3.8)	success	✅
install-pkg (ubuntu-22.04, pytorch, 3.11)	success	✅
install-pkg (ubuntu-22.04, lightning, 3.8)	success	✅
install-pkg (ubuntu-22.04, lightning, 3.11)	success	✅
install-pkg (ubuntu-22.04, notset, 3.8)	success	✅
install-pkg (ubuntu-22.04, notset, 3.11)	success	✅
install-pkg (macOS-12, app, 3.8)	success	✅
install-pkg (macOS-12, app, 3.11)	success	✅
install-pkg (macOS-12, fabric, 3.8)	success	✅
install-pkg (macOS-12, fabric, 3.11)	success	✅
install-pkg (macOS-12, pytorch, 3.8)	success	✅
install-pkg (macOS-12, pytorch, 3.11)	success	✅
install-pkg (macOS-12, lightning, 3.8)	success	✅
install-pkg (macOS-12, lightning, 3.11)	success	✅
install-pkg (macOS-12, notset, 3.8)	success	✅
install-pkg (macOS-12, notset, 3.11)	success	✅
install-pkg (windows-2022, app, 3.8)	success	✅
install-pkg (windows-2022, app, 3.11)	success	✅
install-pkg (windows-2022, fabric, 3.8)	success	✅
install-pkg (windows-2022, fabric, 3.11)	success	✅
install-pkg (windows-2022, pytorch, 3.8)	success	✅
install-pkg (windows-2022, pytorch, 3.11)	success	✅
install-pkg (windows-2022, lightning, 3.8)	success	✅
install-pkg (windows-2022, lightning, 3.11)	success	✅
install-pkg (windows-2022, notset, 3.8)	success	✅
install-pkg (windows-2022, notset, 3.11)	success	✅

These checks are required after the changes to src/lightning/data/streaming/reader.py.

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Thank you for your contribution! 💜

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