[<prev] [next>] [<thread-prev] [day] [month] [year] [list]
Message-ID: <20130702201644.GA31312@openwall.com>
Date: Wed, 3 Jul 2013 00:16:44 +0400
From: Solar Designer <solar@...nwall.com>
To: john-dev@...ts.openwall.com
Subject: Re: bug: GPU use in CPU-only formats
On Tue, Jul 02, 2013 at 08:47:27PM +0400, Solar Designer wrote:
> On Tue, Jul 02, 2013 at 11:53:31AM -0300, Claudio Andr? wrote:
> > BUT: no real GPU memory allocation is done inside common code. Neither
> > code execution. So, ghosts and busy devices could not happen.
>
> Somehow the NVIDIA card and the PSU actually get hotter because of this;
> I wonder what's going on in there if not code execution. I think it's
> at least 100W extra (roughly half-load on the card), compared to running
> a CPU-only build with the same format.
Here's a guess: it's clock rate increase. Normally, the GPU idles at a
much reduced clock rate, but after OpenCL initialization it's probably
idling (executing some idle loop?) at the full clock rate.
Alexander
Powered by blists - more mailing lists
Confused about mailing lists and their use?
Read about mailing lists on Wikipedia
and check out these
guidelines on proper formatting of your messages.
