On Mon, Sep 27, 2021 at 6:58 PM Eric Snow
We've frozen most of the stdlib modules imported during "python -c pass" , to make startup a bit faster. Import of those modules is controlled by "-X frozen_modules=[on|off]". Currently it defaults to "off" but we'd like to default to "on". The blocker is the impact on contributors. I expect many will make changes to a stdlib module and then puzzle over why those changes aren't getting used. That's an annoyance we can avoid, which is the point of this thread.
1. always default to "on" (the annoyance for contributors isn't big enough?) 2. default to "on" if it's a PGO build (and "off" otherwise) 3. default to "on" unless running from the source tree
Honestly, for me, #1: always on, is the most reasonable choice. I dislike when Python behaves differently depending on subtle things like "was it built with optimizations" or "is Python started from its source tree"? When I built Python without optimization and/or from its source tree, I do that to debug an issue. If the bug goes away in this case, it can waste my time. So I prefer to teach everybody how to use "-X frozen_modules=off" if they want to hack the stdlib for their greatest pleasure. I prefer that such special use case requires an opt-in option, the special use case is not special enough to be the default. -- It means that the site module module can no longer be "customized" by modifying directly the site.py file (inject a path in PYTHONPATH env var where the customized site.py lives). But there is already a supported way to customize the site module: create a module named "sitecustomize" or "usercustomizer". I recall that virtualenv likes to override stdlib site.py with its own code. tox uses virtualenv by default. Someone should check if freezing site doesn't break virtualenv and tox, since they seem to be popular in Python. The venv doesn't need to override site.py and tox can use venv if I recall correctly. If site.py customization is too popular, I would suggest to not freeze this one, until the community stops doing that. Victor -- Night gathers, and now my watch begins. It shall not end until my death.