[Python-Dev] Caching float(0.0)

"Martin v. Löwis" martin at v.loewis.de
Tue Oct 3 14:25:38 CEST 2006

Nick Craig-Wood schrieb:
> Even if 0.0 is allocated and de-allocated 10,000 times in a row, there
> would be no memory savings by caching its value.
> However there would be
> a) less allocator overhead - allocation objects is relatively expensive
> b) better caching of the value
> c) less cache thrashing
> I think you'll find that even in the no memory saving case a few
> cycles spent on comparison with 0.0 (or maybe a few other values) will
> speed up programs.

Can you demonstrate that speedup?

It is quite difficult to anticipate the performance impact of a change,
in particular if there is no change in computational complexity. Various
effects tend to balance out each other.


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