DEPR: deprecate fastpath keyword in Index constructors by jorisvandenbossche · Pull Request #23110 · pandas-dev/pandas (original) (raw)

Relatively it is a big difference:

In [8]: values = np.arange(100000)

In [9]: %timeit pd.Index(values)
31 µs ± 140 ns per loop (mean ± std. dev. of 7 runs, 10000 loops each)

In [10]: %timeit pd.Index._simple_new(values)
1.62 µs ± 26.1 ns per loop (mean ± std. dev. of 7 runs, 1000000 loops each)

but if that will be significant in actual code, I don't know.

But since we are using that in many places, I leave changing _simple_new calls to the public constructor for another PR.