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Date: Mon, 5 Jan 2009 12:08:19 -0800
From: malahal@us.ibm.com
Subject: Re: [linux-lvm] LVM2 on-disk layout
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Stuart D. Gathman [stuart@bmsi.com] wrote:
> > 3) Why the metadata inside MDA wraps around, instead of the offset
> > pointing to the start of metadata?
> 
> Someone else?

Probably because when something bad happens while changing the metadata,
you want to go back to the old state. To preserve the old state, you
don't want to wipe the old metadata. You need offset other than the
start of the metadata! Circular buffer is an optimal solution to
implement this, I guess.