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From: Victor Engmark <victor.engmark@terreactive.ch>
To: Jeff King <peff@peff.net>
Cc: "Jonathan Nieder" <jrnieder@gmail.com>,
	"vinassa vinassa" <vinassa.vinassa@gmail.com>,
	git@vger.kernel.org, "Ævar Arnfjörð Bjarmason" <avarab@gmail.com>
Subject: Re: git behaviour question regarding SHA-1 and commits
Date: Mon, 14 Nov 2011 13:48:51 +0100	[thread overview]
Message-ID: <20111114124851.GB21854@victor> (raw)
In-Reply-To: <20111114113235.GE10847@sigill.intra.peff.net>

On Mon, Nov 14, 2011 at 06:32:35AM -0500, Jeff King wrote:
> On Sun, Nov 13, 2011 at 12:27:57PM -0600, Jonathan Nieder wrote:
> 
> > Though I haven't tested.  It would be nice to have an md5git (or even
> > truncated-sha1-git) program to test this kind of thing with.
> 
> Fortunately we have such a thing:
> 
>   http://article.gmane.org/gmane.comp.version-control.git/184243
> 
> That one actually has 40 bits of hash entropy, so you'd expect to
> generate 2^20 (about a million) commits before accidentally colliding.
> If you want an easier experiment, you could truncate it even further.

Would it be helpful to truncate this to something ludicrous like a
single byte of entropy, to be able to write tests for the various tools
and options?

Cheers,
V

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  reply	other threads:[~2011-11-14 12:49 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-11-13 17:04 git behaviour question regarding SHA-1 and commits vinassa vinassa
2011-11-13 17:41 ` Ævar Arnfjörð Bjarmason
2011-11-14  3:29   ` Junio C Hamano
2011-11-14 11:48     ` Jeff King
2011-11-13 18:27 ` Jonathan Nieder
2011-11-13 22:14   ` vinassa vinassa
2011-11-14 11:32   ` Jeff King
2011-11-14 12:48     ` Victor Engmark [this message]
2011-11-14 13:04       ` Jeff King
2011-11-13 22:14 ` Dmitry Potapov
2011-11-14  7:39 ` Johannes Sixt

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