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Items tagged python, gil in 2023

Filters: Year: 2023 × python × gil × Sorted by date


A Steering Council notice about PEP 703 (Making the Global Interpreter Lock Optional in CPython) (via) Huge news concerning the nogil research fork of Python: “It’s clear that the overall sentiment is positive, both for the general idea and for PEP 703 specifically. The Steering Council is also largely positive on both. We intend to accept PEP 703, although we’re still working on the acceptance details.” # 29th July 2023, 9:23 pm

The Python Language Summit 2023: Making the Global Interpreter Lock Optional. Extremely informative update covering Sam Gross’s python-nogil proposal from this year’s language summit at PyCon.

Sam has been working hard on his fork for the past year, and now has it rebased for Python 3.12. If his PEP is accepted it could end up as an optional compile-time build in time for Python 3.13.

“The plan for nogil remains that it would be enabled via a compile-time flag, named --disable-gil. Third-party C extensions would need to provide separate wheels for GIL-disabled Python.” # 31st May 2023, 12:04 am

Real Multithreading is Coming to Python—Learn How You Can Use It Now (via) Martin Heinz provides a detailed tutorial on trying out the new Per-Interpreter GIL feature that’s landing in Python 3.12, which allows Python code to run concurrently in multiple threads by spawning separate sub-interpreters, each with their own dedicated GIL.

It’s not an easy feature to play with yet! First you need to compile Python yourself, and then use APIs that are generally only available to C code (but should hopefully become available to Python code itself in Python 3.13).

Martin’s workaround for this is ingenious: it turns out the Python test.support package provides utility functions to help write tests against interpreters, and Martin shows how to abuse this module to launch, run and cleanup interpreters using regular Python code.

He also demonstrates test.support.interpreters.create_channel(), which can be used to create channels with receiver and sender ends, somewhat similar to Go. # 15th May 2023, 7:42 pm

My strong hunch is that the GIL does not need removing, if a) subinterpreters have their own GILs and b) an efficient way is provided to pass (some) data between subinterpreters lock free and c) we find good patterns to make working with subinterpreters work.

Armin Ronacher # 11th April 2023, 4:47 pm

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