From mboxrd@z Thu Jan  1 00:00:00 1970
Message-ID: <9e1383e4ac05c45c5b669d8fd19c7a2c@quanstro.net>
To: weigelt@metux.de, 9fans@cse.psu.edu
Subject: Re: [9fans] thoughs about venti+fossil
From: erik quanstrom <quanstro@quanstro.net>
Date: Thu,  6 Mar 2008 09:35:45 -0500
In-Reply-To: <20080306064002.GD18329@nibiru.local>
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> But for HA applications, we still need some additional redundancy
> or at least some error diagnostics at application level. Well,
> we'll most likely needs this anyways, eg. to detect human fault
> or code bugs.
>
> My current idea is to use two separate hash functions in parallel
> (as many sw distros already do). But I've got no idea if this
> really helps or collissions in SHA-1 will often go parallel with
> colissions in the second hash (eg. MD5).

adding a second hash will likely increase your failure rate as
the failure rate of storage is >> collision rate of sha1.  and
adding a second hash will increase your storage, thus increasing
your exposure to storage failure.

- erik