Mirror/cpython - cpython - Spiri Gitea

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GH-120754: Disable buffering in Path.read_bytes (#122111) `Path.read_bytes()` is used to read a whole file. buffering / BufferedIO is focused around making small, possibly interleaved, read/write efficient which doesn't add value in this case. On my Mac, running the benchmark: ```python import pyperf from pathlib import Path def read_all(all_paths): for p in all_paths: p.read_bytes() def read_file(path_obj): path_obj.read_bytes() all_rst = list(Path("Doc").glob("**/*.rst")) all_py = list(Path(".").glob("**/*.py")) assert all_rst, "Should have found rst files" assert all_py, "Should have found python source files" runner = pyperf.Runner() runner.bench_func("read_file_small", read_file, Path("Doc/howto/clinic.rst")) runner.bench_func("read_file_large", read_file, Path("Doc/c-api/typeobj.rst")) ``` before: ```python ..................... read_file_small: Mean +- std dev: 6.80 us +- 0.07 us ..................... read_file_large: Mean +- std dev: 10.8 us +- 0.2 us ```` after: ```python ..................... read_file_small: Mean +- std dev: 5.67 us +- 0.05 us ..................... read_file_large: Mean +- std dev: 9.77 us +- 0.52 us ```

2024-08-16 17:52:41 -03:00

``Pathlib.read_bytes`` no longer opens the file in Python's buffered I/O mode. This reduces overheads as the code reads a file in whole leading to a modest speedup.