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Date: Fri, 17 Oct 2003 10:16:29 -0400
From: Jeff Garzik <jgarzik@pobox.com>
To: jlnance@unity.ncsu.edu
Cc: linux-kernel@vger.kernel.org
Subject: Re: Transparent compression in the FS
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On Fri, Oct 17, 2003 at 09:07:29AM -0400, jlnance@unity.ncsu.edu wrote:
> On Thu, Oct 16, 2003 at 06:47:15PM -0700, Eric Sandall wrote:
> 
> > It doesn't really matter that the hash collision is /less/ likely to ruin data
> > than something in hardware as it adds an /extra/ layer of possible corruption,
> > so you have a net gain in the possible corruption of your data.  Now, if you
> > could write it so that there was /no/ possibility of data corruption, than it
> > would be much more acceptable as it wouldn't add any extra likeliness of
> > corruption than already exists.
> 
> This assumes that the probability of there being a bug in the code which
> checks for identical blocks is less than the probability of a hash collision.
> I am not sure that is a good assumption.

The complexity of a memcmp() is pretty low...