[vlovich123]

All the GILectomy plans IIRC also include single threaded performance improvements to offset any such costs. So while performance vs GIL is maybe worse for single threaded for the same Python version, performance will still be ahead of where it is today for single-threaded python (assuming everything goes according to plan). That's also why multi-threaded performance will be more than just existing perf * number of cores (vs what it is today, not what removing the GIL alone provides).

[eviks]

But it doesn't offset anything since you get all the other improvements anyway, they're not tied to gil/nogil

[vlovich123]

I could be misremembering, but I thought that the MSFT team proposed those performance improvements specifically to offset any concerns about single threaded performance degradation from removing the GIL. Thus even if development is happening in parallel by independent (which I thought it wasn't - I thought it was all 1 team doing this work), it was predicated upon nogil being accepted in the first place. Thus if GIL were to remain in Python, then this performance work wouldn't be happening.

[eviks]

Maybe the work wouldn't be happening without the noGIL work, but once it's happened it's not tied to the GIL, you can pick those improvements and continue with a GIL-only Python

[vlovich123]

This post is literally about step 1: add this behind an unsupported experimental flag to get more insights. Step 2 is mid-term to make it a supported option based on readiness (within another 2 years). Step 3 is making it the default & then removing the GIL [1]. Steps 2 and 3 may not happen if some major unsolvable obstacle appears. But I doubt it's going to be so easy to reverse this direction. Given MSFT is driving all of this right now, it's hard to imagine there's going to be much appetite to break their trust; MSFT is more likely to cut funding before completion which would create some chaos than the steering committee is to violate an agreement around funding (MSFT has made specific long term commitments they're going to keep, but those commitments are only for a few years IIRC).

[1] https://developer.vonage.com/en/blog/removing-pythons-gil-it...

[Sakos]

Why is MSFT so interested in funding this?

[robertlagrant]

MSFT are keen to invest in popular development tools such as Python, Javascript, and Git. They hired Guido; they bought NPM; they bought GitHub.

I don't know what the plan is, but they haven't succeeded (outside of the corporate world, really, for C# and the functional world in F#) in making modern tooling and languages people want to use.