Some context from one of the replies to that tweet:
> This is a graph of CPU utilization for the web services that power PyPI. Today we upgraded from 3.10 to 3.11 and saw a significant and correlated drop in CPU usage -- nearly half.
>
> The CPython team has been putting a lot of effort into improving performance recently and it shows!
If you're talking about the older approach to implementation CPython used to take then I must say if was pretty efficient for what it did (all while keeping the code clean). It took a 2-3 days deep dive for a moderately prepared programmer to understand ins/outs of the interpreter.
Optimisations coming to Python are a departure from the "clean-first code" approach. It's performance coming at a price of complexity.
> This is a graph of CPU utilization for the web services that power PyPI. Today we upgraded from 3.10 to 3.11 and saw a significant and correlated drop in CPU usage -- nearly half.
>
> The CPython team has been putting a lot of effort into improving performance recently and it shows!