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Date: Sat, 2 Feb 2013 19:25:33 +0400
From: Solar Designer <solar@...nwall.com>
To: john-dev@...ts.openwall.com
Subject: Re: NetNTLMv1

magnum -

On Fri, Feb 01, 2013 at 07:45:12AM +0400, Solar Designer wrote:
> With a generic+OpenMP build, it is ~3150M c/s for one process (8
> threads).  This puzzles me, because generic's MD4 computations are
> slower, whereas the comparisons are not supposed to be faster since
> OpenMP is only being made use of for the MD4s, not for comparisons, in
> that code version.  So I would have expected its performance to be
> around ~850M at "many salts" - same as I'm getting for one process with
> the XOP build (on otherwise idle system).  I don't understand where a
> further 4x speedup comes from.

I think I figured this out: generic+OpenMP uses much higher
max_keys_per_crypt than SIMD-enabled non-OpenMP builds do.  Can you
rework the latter to allow for increasing their max_keys_per_crypt?
My gut feeling is that a value of around 0x100 will be optimal (need to
make it a multiple of MMX_COEF and maybe MD4_SSE_PARA as appropriate for
a given build, of course).

Alexander

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