Anthony Sottile <asott...@umich.edu> added the comment:
here's the performance regressions, they affect any callers of `distributions()` and are even worse on callers of the new apis. a call to distributions() is about 3x slower than in 3.9 here is the setup I am using: virtualenv venv39 -ppython3.9 venv39/bin/pip install flake8 pytest twine pre-commit virtualenv venv310 -ppython3.10 venv310/bin/pip install flake8 pytest twine pre-commit to test just the `distributions()` call I'm using the following: ```console $ venv39/bin/python -m timeit -n 20 -r 20 -s 'from importlib.metadata import entry_points' 'entry_points()' 20 loops, best of 20: 12.5 msec per loop $ venv310/bin/python -m timeit -n 20 -r 20 -s 'from importlib.metadata import entry_points' 'entry_points()' 20 loops, best of 20: 36.7 msec per loop ``` this is a less-extreme example, many applications have more dependencies installed -- but even in this case this is adding ~24ms startup to any application using `entry_points()` -- and it gets worse the return value of `entry_points()` alone isn't all that useful, next an application needs to retrieve its entry points. let's start for the somewhat normal case of retrieving a single category of entry points: ```console $ venv39/bin/python -m timeit -n 20 -r 20 -s 'from importlib.metadata import entry_points' 'entry_points()["flake8.extension"]' 20 loops, best of 20: 12.7 msec per loop $ venv310/bin/python -m timeit -n 20 -r 20 -s 'from importlib.metadata import entry_points' 'entry_points(name="flake8.extension")' 20 loops, best of 20: 37.1 msec per loop $ venv310/bin/python -m timeit -n 20 -r 20 -s 'from importlib.metadata import entry_points' 'entry_points().select(group="flake8.extension")' 20 loops, best of 20: 37.1 msec per loop ``` again, 3x slower and very real time to the end user (~24-25ms) now let's show an example usage that something like flake8 uses where multiple groups are requested (this is common for apps and plugin systems which provide multiple distinct functionalities) ```console $ venv39/bin/python -m timeit -n 20 -r 20 -s 'from importlib.metadata import entry_points' 'eps = entry_points(); eps["flake8.extension"]; eps["flake8.report"]' 20 loops, best of 20: 12.6 msec per loop $ venv310/bin/python -m timeit -n 20 -r 20 -s 'from importlib.metadata import entry_points' 'eps = entry_points(); eps.select(group="flake8.extension"); eps.select(group="flake8.report")' 20 loops, best of 20: 38.2 msec per loop ``` also slower, but an additional ms per call to `.select(...)` and it only gets worse with more and more packages installed here's the versions I'm using to ensure they are up to date: ```console $ venv39/bin/python --version --version Python 3.9.5 (default, May 19 2021, 11:32:47) [GCC 9.3.0] $ venv310/bin/python --version --version Python 3.10.0b2 (default, Jun 2 2021, 00:22:18) [GCC 9.3.0] ``` ---------- resolution: fixed -> status: closed -> open _______________________________________ Python tracker <rep...@bugs.python.org> <https://bugs.python.org/issue44246> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
