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SubjectRe: [RFC][PATCH] Faster generic_fls
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Linus Torvalds <torvalds@transmeta.com> writes:

> Classic mistake. Lookup tables are only faster in benchmarks, they
> are almost always slower in real life. You only need to miss in the
> cache _once_ on the lookup to lose all the time you won on the
> previous one hundred calls.

It seems to me if you call the function so seldom the table drops out
of the cache, it is irrelevant how long it takes anyway.

> "Small and simple" is almost always better than the alternatives.

Well, if a lookup table isn't "small and simple", I don't know what
is.

--
Falk
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