GNU bug report logs - #6789
propose renaming gnulib memxfrm to amemxfrm (naming collision with coreutils)

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Message #38 received at submit <at> debbugs.gnu.org (full text, mbox):

From: Simon Josefsson <simon <at> josefsson.org>
To: Paul Eggert <eggert <at> CS.UCLA.EDU>
Cc: Bug-coreutils <bug-coreutils <at> gnu.org>, Paolo Bonzini <bonzini <at> gnu.org>,
	bug-gnulib <at> gnu.org
Subject: Re: propose renaming gnulib memxfrm to amemxfrm (naming collision
	with coreutils)
Date: Sat, 07 Aug 2010 13:40:46 +0200

Paul Eggert <eggert <at> CS.UCLA.EDU> writes:

> On 08/06/10 01:22, Paolo Bonzini wrote:
>> ISAAC is a RNG, so wouldn't that have the same problem above?  You
>> definitely need to use a hash function, it's just that you do not need a
>> cryptographic one.
>
> I had been thinking of using ISAAC by making the key its seed, and
> asking it to generate some random values, and then comparing the
> random values.  Any RNG can be used (or abused :-) in this way.
>
> I just now tried, that, though, and discovered that on my million line
> benchmark the MD5 method is about 4 times faster than the ISAAC-based
> method.  So that idea was not a good one.  I suppose we could try a
> non-cryptographic hash function at some point.

I suspect FNV or Xorshift would be faster, since they are so simple:

http://en.wikipedia.org/wiki/Fowler_Noll_Vo_hash
http://en.wikipedia.org/wiki/Xorshift

/Simon

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