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Date: Tue, 29 Mar 2011 20:45:35 +0200
From: magnum <rawsmooth@...dband.net>
To: john-dev@...ts.openwall.com
Subject: Re: john scalability

On 2011-03-29 18:22, Solar Designer wrote:
> On Mon, Mar 28, 2011 at 09:19:20PM +0200, magnum wrote:
>> So here it is, suggested for the Jumbo. This patches all formats that
>> had only three sizes (except AFS), extending them to have five.
>
> Thanks!
>
> A related concern, though, is that the self-tests only check that the
> values are in range - they don't check for full usage of the range, nor
> for uniform distribution.  So it is easy to have a bug where a large
> hash table would be allocated, but only a subset of its hash buckets
> would ever be in use.

True, I have not tested all formats with real hashes and debug code. I 
would like to dump distribution statistics after loading, but I'm not 
sure how to accomplish that quick and easy. That would be a very nice 
"#ifdef'ed patch" though, to use for future testing. It could also be 
used to ensure that the current formats, even without the larger sizes, 
do the right thing. It would also be useful if trying to implement these 
functions from scratch in all the formats lacking it.

Even if we had such debug code in place, I lack sufficiently sized input 
files for many of the formats.

I did however take a brief look at all of the formats confirming it 
*seemed* to make sense just adding the wider bitmasks.

magnum

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