https://github.com/python/cpython/commit/f1574859d7d6cd259f867194762f04b72ef... commit: f1574859d7d6cd259f867194762f04b72ef2c340 branch: main author: Sam Gross <colesbury@gmail.com> committer: colesbury <colesbury@gmail.com> date: 2025-01-03T21:48:47Z summary: gh-125985: Fix `cmodule_function()` scaling benchmark (#128460) Add a separate benchmark that measures the effect of `_PyObject_LookupSpecial()` on scaling. In the process of cleaning up the scaling benchmarks for inclusion, I unintentionally changed the "cmodule_function" benchmark to pass an `int` to `math.floor()` instead of a `float`, which causes it to use the `_PyObject_LookupSpecial()` code path. `_PyObject_LookupSpecial()` has its own scaling issues that we want to measure separately from calling a function on a C module. files: M Tools/ftscalingbench/ftscalingbench.py diff --git a/Tools/ftscalingbench/ftscalingbench.py b/Tools/ftscalingbench/ftscalingbench.py index 767aeae9349070..364c465bc91b0b 100644 --- a/Tools/ftscalingbench/ftscalingbench.py +++ b/Tools/ftscalingbench/ftscalingbench.py @@ -54,8 +54,16 @@ def object_cfunction(): @register_benchmark def cmodule_function(): - for i in range(1000 * WORK_SCALE): - math.floor(i * i) + N = 1000 * WORK_SCALE + for i in range(N): + math.cos(i / N) + +@register_benchmark +def object_lookup_special(): + # round() uses `_PyObject_LookupSpecial()` internally. + N = 1000 * WORK_SCALE + for i in range(N): + round(i / N) @register_benchmark def mult_constant(): @@ -206,7 +214,7 @@ def benchmark(func): color = "\x1b[33m" # yellow reset_color = "\x1b[0m" - print(f"{color}{func.__name__:<18} {round(factor, 1):>4}x {direction}{reset_color}") + print(f"{color}{func.__name__:<25} {round(factor, 1):>4}x {direction}{reset_color}") def determine_num_threads_and_affinity(): if sys.platform != "linux":