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Date: Tue, 19 Jun 2012 09:48:06 +0200
From: Tavis Ormandy <taviso@...xchg8b.com>
To: john-dev@...ts.openwall.com
Subject: Re: Re: [patch] optional new raw sha1 implemetation

On Sun, Jun 17, 2012 at 04:45:59PM +0200, Tavis Ormandy wrote:
> On Sun, Jun 17, 2012 at 04:24:43PM +0200, magnum wrote:
> > Nice, you boosted it by 13% on my core2 laptop.
> 
> Great news! I'll experiment with a few other ideas.
> 

I noticed that one of the problems with setting it too high was that
John calls cmp_one for every hash after a successful cmp_all. cmp_one
really hurts, so if max_keys_per_crypt is too high, I lose some of the
benefit to the overhead when there is a partial match.

I noticed an easy way to fix it is just to check if get_hash() ==
binary_hash() first, I sent you a pull request to add that. But would
that work in general for all the other hashes?

It might matter in the cases where you have high max_keys_per_crypt, and
very fast hashes. I didn't check if anyone else is doing that, but maybe
they will in future :-)

Tavis.

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