ref: replace inspect.stack() with a more performant iteration of the current stack

[asottile-sentry]

inspect.stack() in python 3.11 is about 15x slower than in 3.10

the new function I made is even faster than inspect.stack even in 3.10

little benchmark scripty

Details

import sys
import inspect
import time
from typing import Generator


def _current_stack_filenames() -> Generator[str, None, None]:
    f = sys._getframe()
    while f is not None:
        yield f.f_code.co_filename
        f = f.f_back


def _current_stack_filenames_inspect() -> Generator[str, None, None]:
    for _, filename, _, _, _, _ in inspect.stack():
        yield filename


def j():
    l1 = list(_current_stack_filenames())
    l2 = list(_current_stack_filenames_inspect())
    assert l1 == l2, (l1, l2)

    t1 = time.monotonic() + 5
    i = 0
    while time.monotonic() < t1:
        tuple(_current_stack_filenames())
        i += 1

    print(f'new: {i}')

    t1 = time.monotonic() + 5
    i = 0
    while time.monotonic() < t1:
        tuple(_current_stack_filenames_inspect())
        i += 1

    print(f'old: {i}')



def i():
    j()


def h():
    i()


def g():
    h()


def f():
    g()


def test():
    f()


def main():
    f()


if __name__ == '__main__':
    raise SystemExit(main())

$ python3.10 t6.py 
new: 6267307
old: 51673
$ : 121x speedup in 3.10

$ python3.11 t6.py 
new: 7993958
old: 44539
$ : 179x speedup in 3.11

[mwarkentin]

Some reference as to why this is needed:

• Slow inspect.getmodule python/cpython#92041 (comment)
• gh-92041: Avoid module scans for frames and tracebacks python/cpython#92042

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (4e55b40) 81.39% compared to head (ea711ea) 81.40%.
Report is 33 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff           @@
##           master   #63965   +/-   ##
=======================================
  Coverage   81.39%   81.40%           
=======================================
  Files        5228     5228           
  Lines      232470   232509   +39     
  Branches    40253    40254    +1     
=======================================
+ Hits       189222   189264   +42     
- Misses      37396    37397    +1     
+ Partials     5852     5848    -4     

Files	Coverage Δ
src/sentry/options/defaults.py	100.00% <100.00%> (ø)
src/sentry/relay/globalconfig.py	88.88% <ø> (ø)
src/sentry/utils/sdk.py	71.18% <100.00%> (+0.61%)	⬆️

... and 19 files with indirect coverage changes

[joshuarli]

👀