[Python-Dev] Benchmarks why we need PEP 576/579/580

[Stefan Behnel]

Guido van Rossum schrieb am 21.07.2018 um 22:46:
> Given the cost of a mistake here I recommend a higher standard.

May I ask what you think the "cost of a mistake" is here?

Jeroen has already implemented most of this, and is willing to provide
essentially a shrink-wrapped implementation. He has shown, using the
current application benchmark suite, that his implementation does not
degrade the application performance (that we know of). He has motivated in
PEP form, and shown in his implementation, that the changes avoid much of
the special casing that's currently littered in various spots of the
interpreter and replace them by a much clearer protocol, thus reducing the
overall maintenance cost. He has layed out a cleanup path to get rid of the
current quirks in the split between function/method types, thus making the
code easier to explain and lowering the entry barrier for newcomers to the
code base. And, he has motivated that this protocol enables a future
extension towards a specialised (faster) C level call protocol, which third
party extensions would benefit from.

Given all that, I'm having a hard time finding a "cost" in this. To me, it
reads like a plain net win for all sides.

Stefan