Openwall GNU/*/Linux - a small security-enhanced Linux distro for servers
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date: Sat, 22 Sep 2012 09:39:53 +0400
From: Solar Designer <solar@...nwall.com>
To: john-dev@...ts.openwall.com
Subject: Re: bitslice DES on GPU

On Sat, Sep 22, 2012 at 10:58:50AM +0530, Sayantan Datta wrote:
> I gave it a detailed thought to your calculations. In fact doubling the
> work items shouldn't affect the speeds anyway. for example:
> 
> H c/s = W/(O+C) : where W = no. of work items
>                                       O = time spent on overhead.
>                                       C  = time spent on actual
> (non-overhead) hashing.
>                                       H = actual real world speed.
> So if W is doubled , O and C should get doubled automatically as both O and
> C are proportional to W.

This sounds right to me.

> What happened is that I manged to reduce the overhead (using different
> code) while slowing down the actual hashing(using different kernel).

OK.

> Anyway  I managed to improve the non-overhead speeds to 59M c/s using
> nvidia s-boxes and putting B[] in private register space on 7970.

Good.  We're getting somewhere.

> AMD s-boxes aren't working .

In what way are they non-working?

Thanks,

Alexander

Powered by blists - more mailing lists

Your e-mail address:

Powered by Openwall GNU/*/Linux - Powered by OpenVZ