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The first year of free-threaded Python

(labs.quansight.org)
255 points rbanffy | 2 comments | 16 May 25 09:42 UTC | HN request time: 0.422s | source
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AlexanderDhoore ◴[16 May 25 11:03 UTC] No.44003888[source]▶
Am I the only one who sort of fears the day when Python loses the GIL? I don't think Python developers know what they’re asking for. I don't really trust complex multithreaded code in any language. Python, with its dynamic nature, I trust least of all.
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miohtama ◴[16 May 25 11:13 UTC] No.44003943[source]▶
GIL or no-GIL concerns only people who want to run multicore workloads. If you are not already spending time threading or multiprocessing your code there is practically no change. Most race condition issues which you need to think are there regardless of GIL.
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1. fulafel ◴[16 May 25 13:55 UTC] No.44005583[source]▶
A lot of Python usage is leveraging libraries with parallel kernels inside written in other languages. A subset of those is bottlenecked on Python side speed. A sub-subset of those are people who want to try no-GIL to address the bottleneck. But if non-GIL becomes pervasive, it could mean Python becomes less safe for the "just parallel kernels" users.
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2. kccqzy ◴[16 May 25 14:12 UTC] No.44005769[source]▶
Yes sure. Thought experiment: what happens when these parallel kernels suddenly need to call back in to Python? Let's say you have a multithreaded sorting library. If you are sorting numbers then fine nothing changes. But if you are sorting objects you need to use a single thread because you need to call PyObject_RichCompare. These new parallel kernels will then try to call PyObject_RichCompare from multiple threads.