kolja005 4 daysReload

I recently watched a talk by the author of uv that was surprisingly fascinating [1]. He goes into a few of the more notable hacks that they had to come up with to make it as fast as it is. The most interesting thing for me was that package resolution in python given constraints defined (eg. in requirements.txt) maps to a boolean satisfiability problem which is NP-complete. So uv uses a custom SAT solver to do this. I totally under-appreciated how much goes into this software and I'm bummed I have to use Poetry at work after having watched this talk.

[1] https://www.youtube.com/watch?v=gSKTfG1GXYQ

edit: NP-complete not NP-hard

thundergolfer 4 daysReload

Kind of an aside as this doc is about the complexities of installing particular PyTorch versions, but will say that uv is way faster at installing PyTorch than pip.

We run internal benchmarks of our custom container image builder and in the 'install torch' benchmark the p50 time saved when using `uv` is 25 seconds! (71.4s vs. 43.74s)

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Aside 2: Seems there's a missing "involves" in this sentence: "As such, installing PyTorch typically often configuring a project to use the PyTorch index."

gdiamos 4 daysReload

uv significantly speeds up my pytorch in docker builds

  # Setup virtual env
  ENV VIRTUAL_ENV=/app/.venv
  ENV PATH="$VIRTUAL_ENV/bin:$PATH"
  RUN python3 -m venv $VIRTUAL_ENV
  RUN . $VIRTUAL_ENV/bin/activate

  # install using uv
  RUN pip install uv
  RUN uv pip install torch==${TORCH_VERSION} --index-url https://download.pytorch.org/whl/cpu

The index-url makes it really convenient.

pcwelder 3 daysReload

I just want to thank people behind uv. The tool is just amazing for development, packaging and running packages. And it's blazing fast!

minimaxir 4 daysReload

So uv caused a bit of an issue with me installing PyTorch over the weekend.

When installed with brew on my MacBook, uv currently has PyTorch 3.13 as a dependency, which is fine. But PyTorch does not currently have a stable wheel that's compatable with Python 3.13! This resulted in very confusing errors. (Solution was to point to the Nightly index)

That's technically PyTorch's fault, but it's indicitave why a specific page on installing PyTorch is necessary, and it's good to know the documentation specifically calls it out.