Re: [PATCH 2/3] [CRYPTO] Add optimized SHA-1 implementation for i486+

Andi Kleen
2007-06-11T11:08:09Z

Matt Mackall <mpm@selenic.com> writes:
>
> Have you benchmarked this against lib/sha1.c? Please post the results.
> Until then, I'm frankly skeptical that your unrolled version is faster
> because when I introduced lib/sha1.c the rolled version therein won by
> a significant margin and had 1/10th the cache footprint.

I would always suggest to benchmark such functions with forced cold i/d caches

(memset(x, 0, 5*1024*1024) and running some very large generated
function every few iterations of the benchmark)

-Andi