Openwall GNU/*/Linux - a small security-enhanced Linux distro for servers
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date: Sun, 23 Sep 2012 17:53:42 +0530
From: Sayantan Datta <std2048@...il.com>
To: john-dev@...ts.openwall.com
Subject: Re: bitslice DES on GPU

On Sun, Sep 23, 2012 at 4:00 PM, magnum <john.magnum@...hmail.com> wrote:

> On 22 Sep, 2012, at 13:42 , Sayantan Datta <std2048@...il.com> wrote:
>
> > Actually the bitselect is causing problems. So I'm removing it along
> with the AMD sboxes for now. Without bitselect, AMD sboxes are slower than
> nv sboxes. I've posted the patch to unstable-jumbo branch of JtR repo.
>
> Testing this on OSX w/ nvidia:
>
> $ ../run/john -t -fo:des-opencl
> OpenCL platform 0: Apple, 2 device(s).
> Using device 1: GeForce GT 650M
> Compilation log: <program source>:292:65: warning: unknown attribute
> 'max_constant_size' ignored
>  __kernel void DES_bs_25(constant uint *index768
> __attribute__((max_constant_size(3072))), __global int *index96 ,__global
> DES_bs_transfer *DES_bs_all,__global DES_bs_vector *B_global)
>                                                                 ^
>
> Benchmarking: DES BS [128/128 BS SSE2-16]... DONE
> Many salts:     2016K c/s real, 2036K c/s virtual
> Only one salt:  2097K c/s real, 2114K c/s virtual
>
> Do you think the compiler warning means we're in trouble or is it OK that
> the attribute is ignored on some systems?
>

Actually it is intended for AMD GPUs but fortunately it is just ignored for
any other GPUs or CPUs without causing any trouble.


>
> Before this patch it was a lot slower:
>

> $ ../run/john -t -fo:des-opencl
> OpenCL platform 0: Apple, 2 device(s).
> Using device 1: GeForce GT 650M
> Benchmarking: DES BS [128/128 BS SSE2-16]... DONE
> Many salts:     173605 c/s real, 173893 c/s virtual
> Only one salt:  173318 c/s real, 173605 c/s virtual
>
> The [128/128 BS SSE2-16] is very confusing, it should say OpenCL instead
> of SSE2. Please fix that.
>
> magnum
>

Yeah, sure.

Regards,
Sayantan

[ CONTENT OF TYPE text/html SKIPPED ]

Powered by blists - more mailing lists

Your e-mail address:

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