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0 pointslopuhin1y ago0 comments

I think GraalPython does have a GIL, see https://github.com/oracle/graalpython/blob/master/docs/contr... - and if by "there is no such thing on those platforms" you mean JVM/CLR not having a GIL, C also does not have a GIL but CPython does.

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pjmlp1y ago

My mistake, as I assumed they took the same decision as jython and IronPython.

https://jython.readthedocs.io/en/latest/Concurrency/#no-glob...

https://wiki.python.org/moin/IronPython

The difference between JVM, CLR and C in regards to parallel and concurrent code is that they are built for those kind of workloads, and have a memory model proper, hence not needing a GIL.

commodoreboxer1y ago

I think they would have to here, to support native modules. Jython (and I believe IronPython, but don't quote me) does not support native CPython modules. CPython modules explicitly control the GIL, so if they are supported (as they are here), you can't really leave the GIL out without exposing potential thread safety issues.

westurner1y ago

"PEP 703 – Making the Global Interpreter Lock Optional in CPython" (2023) https://peps.python.org/pep-0703/

CPython built with --disable-gil does not have a GIL (as long as PYTHONGIL=0 and all loaded C extensions are built for --disable-gil mode) https://peps.python.org/pep-0703/#py-mod-gil-slot

"Intent to approve PEP 703: making the GIL optional" (2023) https://news.ycombinator.com/item?id=36913328#36917709 https://news.ycombinator.com/item?id=36913328#36921625

kaashif1y ago

This is pretty beside the point. The point is that X not having a GIL doesn't inherently mean Python on X also doesn't have a GIL.

westurner1y ago

CPython does not have a GIL Global Interpreter Lock GC Garbage Collection phase with --gil-disabled. GraalVM does have a GIL, like CPython without --gil-disabled.

How CPython accomplished nogil in their - the original and reference - fork is described in the topical linked PEP 703.

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pjmlp1y ago

My mistake, as I assumed they took the same decision as jython and IronPython.

https://jython.readthedocs.io/en/latest/Concurrency/#no-glob...

https://wiki.python.org/moin/IronPython

The difference between JVM, CLR and C in regards to parallel and concurrent code is that they are built for those kind of workloads, and have a memory model proper, hence not needing a GIL.

commodoreboxer1y ago

westurner1y ago

"PEP 703 – Making the Global Interpreter Lock Optional in CPython" (2023) https://peps.python.org/pep-0703/

CPython built with --disable-gil does not have a GIL (as long as PYTHONGIL=0 and all loaded C extensions are built for --disable-gil mode) https://peps.python.org/pep-0703/#py-mod-gil-slot

"Intent to approve PEP 703: making the GIL optional" (2023) https://news.ycombinator.com/item?id=36913328#36917709 https://news.ycombinator.com/item?id=36913328#36921625

kaashif1y ago

This is pretty beside the point. The point is that X not having a GIL doesn't inherently mean Python on X also doesn't have a GIL.

westurner1y ago

CPython does not have a GIL Global Interpreter Lock GC Garbage Collection phase with --gil-disabled. GraalVM does have a GIL, like CPython without --gil-disabled.

How CPython accomplished nogil in their - the original and reference - fork is described in the topical linked PEP 703.

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