Message-ID: <4742825F.9000109@zytor.com>
Date: Mon, 19 Nov 2007 22:44:47 -0800
From: "H. Peter Anvin" <hpa@zytor.com>
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CC: linux-kernel@vger.kernel.org
Subject: Re: [PATCH] Time-based RFC 4122 UUID generator
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David Schwartz wrote:
> 
> Any UUID generator that can produce duplicate UUIDs with probability
> significantly less than purely random UUIDs is so badly broken that it
> should not ever be used. Anyone who finds such a UUID generator should
> immediately either fix it or throw it on the junk heap. Anyone who knowingly
> uses such a UUID generator should be publically shamed.
> 
> Rather than (or at the very least, in addition to) adding a new UUID
> generator, let's fix the one(s) we have.
> 

I presume you mean "significantly higher."

Realistically speaking, a random UUID is probably the best you're going 
to ever get.  I highly suspect that any time- and MAC-address-based 
solution is going to suffer from mis-set clocks and misprogrammed MAC 
addresses more often than you will have collisions in a 122-bit random 
number.

	-hpa
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