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datetime.replace() is very slow #112919
Description
Bug report
Bug description:
datetime.replace() is very slow when called with keyword arguments. For example, with python 3.13 from main on my laptop
$ python -m timeit -s "from datetime import datetime; dt = datetime.now()" "dt.replace(microsecond=0)"
500000 loops, best of 5: 501 nsec per loopFor comparison,
$ python -m timeit -s "from datetime import datetime" "datetime.now()"
2000000 loops, best of 5: 150 nsec per loop
$ python -m timeit -s "from datetime import datetime" "datetime(2020, 1, 1, 12, 34, 56, 123456)"
2000000 loops, best of 5: 119 nsec per loopSo calling replace() is over 4x slower than constructing a new datetime from components and over 3x slower than now(), which makes a system call.
CPython versions tested on:
3.9, 3.10, 3.13
Operating systems tested on:
Linux
Activity
pythongh-112919: Speed-up date, time and datetime.replace()
pythongh-112919: Speed-up date, time and datetime.replace()
pythongh-112919: Speed-up datetime, date and time.replace()
pythongh-112919: Speed-up datetime, date and time.replace()
pythongh-112919: Speed-up datetime, date and time.replace()
pythongh-112919: Speed-up datetime, date and time.replace()
gh-112919: Speed-up datetime, date and time.replace() (GH-112921)
serhiy-storchaka commentedon Jan 30, 2024
Thank you for your contribution @eltoder.
I reclassified it as a new feature. It was not that
replace()methods were too slow, it was that constructors were too fast.pythongh-112919: Speed-up datetime, date and time.replace() (pythonGH…
pythongh-112919: Speed-up datetime, date and time.replace() (pythonGH…
[3.12] pythongh-112919: Speed-up datetime, date and time.replace() (p…