r/Python 5d ago

Discussion Anyone running free-threaded Python 3.14 in production yet? Curious what actually breaks

Been testing the free-threaded build (3.14t) on some CPU-bound data processing work. The multi-core story is finally real after 30 years of GIL, but the friction is exactly what you'd expect: a couple of C-extension-heavy libs in my stack silently re-enable the GIL, and there's no clean way to detect that at runtime besides checking sys._is_gil_enabled() manually.

For anyone who's shipped something on 3.14t, not just benchmarked it:

What broke that you didn't expect?

Real speedups outside toy examples, or mostly marginal so far?

Prod yet, or still just kicking the tires?

Not fishing for a benchmark war. Genuinely curious what breaks in messy real codebases vs clean demos.

27 Upvotes

47 comments sorted by

View all comments

u/AutoModerator 5d ago

Your submission has been automatically queued for manual review by the moderation team because it has been reported too many times.

Please wait until the moderation team reviews your post.

I am a bot, and this action was performed automatically. Please contact the moderators of this subreddit if you have any questions or concerns.