#561: TonIO, a Multi-threaded Async Runtime for Python

How many cores does your machine have, 10, 18? Your async Python code uses just one of them. That isn't a bug in asyncio. That's the design, and optimizing event loops to be faster by 20% doesn't change it. So Giovanni Barillari started over. Joe is the creator of Granian, the Rust-based server that powers Talk Python. His new project is TonIO, an async runtime written from scratch for free-threaded Python. Real threads, a handful of primitives instead of asyncio's pile of them, and it flat out refuses to start if the GIL is on.

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Links from the show

Guest
Giovanni Barillari: github.com

Granian: github.com
Hyper: github.com
Free threaded Python: docs.python.org
Sort of: labs.quansight.org
did a whole course: training.talkpython.fm
uvloop: github.com
rloop: github.com
TonIO: github.com
your EuroPython 2026 talk: www.youtube.com
Michael's Cutting Python Web App Memory Over 31% Article: mkennedy.codes

Watch this episode on YouTube: youtube.com
Episode #561 deep-dive: talkpython.fm/561
Episode transcripts: talkpython.fm

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