From: "H. Peter Anvin" <hpa@zytor.com>
To: davids@webmaster.com
Cc: linux-kernel@vger.kernel.org
Subject: Re: [PATCH] Time-based RFC 4122 UUID generator
Date: Mon, 19 Nov 2007 22:44:47 -0800 [thread overview]
Message-ID: <4742825F.9000109@zytor.com> (raw)
In-Reply-To: <MDEHLPKNGKAHNMBLJOLKCECCIFAC.davids@webmaster.com>
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
next prev parent reply other threads:[~2007-11-20 6:46 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-11-18 19:38 [PATCH] Time-based RFC 4122 UUID generator Helge Deller
2007-11-18 21:05 ` Andrew Morton
2007-11-18 21:34 ` Sam Ravnborg
2007-11-18 21:43 ` Helge Deller
2007-11-19 21:56 ` David Schwartz
2007-11-19 22:58 ` Alan Cox
2007-11-20 6:44 ` H. Peter Anvin [this message]
2007-11-20 22:58 ` Helge Deller
2007-11-21 0:20 ` Alan Cox
2007-11-18 21:40 ` Helge Deller
2007-11-20 6:31 ` Matt Mackall
2007-11-20 21:59 ` Helge Deller
2007-11-20 22:55 ` Matt Mackall
2007-11-20 23:11 ` Helge Deller
2007-11-20 23:34 ` Matt Mackall
2007-11-20 23:00 ` Theodore Tso
2007-11-20 23:30 ` Helge Deller
2007-12-10 5:36 ` [e2fsprogs PATCH] Userspace solution to time-based UUID without duplicates Theodore Tso
2007-12-16 21:53 ` Helge Deller
2007-12-17 0:07 ` Theodore Tso
2007-11-20 6:15 ` [PATCH] Time-based RFC 4122 UUID generator Andrew Morton
2007-11-20 22:40 ` Helge Deller
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