Script to check the effect of https://github.com/scipy/scipy/pull/17397 on performance.

upfirdn_timing.py

import subprocess
from timeit import timeit
import numpy as np
import scipy
from scipy.signal import upfirdn, resample_poly
try:
    from scipy.signal._upfirdn_apply import _output_len
except ImportError:
    from scipy.signal._upfirdn import _output_len


def get_git_branch_name():
    result = subprocess.check_output(['git', 'branch', '--show-current'],
                                     cwd='/home/warren/repos/git/forks/scipy')
    return result.decode('ascii').strip()


print(f'{scipy.__version__=}  (branch: {get_git_branch_name()})')

len_h = 127
in_len = 10**6
up = 320
down = 441

n = 25_000_000
result = timeit('_output_len(len_h, in_len, up, down)',
                number=n, globals=globals())
print(f'_output_len:   {result/n*1e9:8.2f} ns')

h = np.full(len_h, fill_value=1/len_h)
x = np.sin(0.1*np.arange(in_len))

n = 2000
result = timeit('upfirdn(h, x, up, down)', number=n, globals=globals())
print(f'upfirdn:       {result/n*1e3:8.2f} ms')

n = 2000
result = timeit('resample_poly(x, up, down)', number=n, globals=globals())
print(f'resample_poly: {result/n*1e3:8.2f} ms')