From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christoph Hellwig <hch@infradead.org>
Subject: Re: [RFC] Metadata Replication for Ext4
Date: Fri, 21 Oct 2011 11:54:28 -0400
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Cc: Aditya Kali <adityakali@google.com>,
	Andreas Dilger <adilger@dilger.ca>,
	Lukas Czerner <lczerner@redhat.com>,
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	Ric Wheeler <rwheeler@redhat.com>,
	"Alasdair G.Kergon" <agk@redhat.com>,
	Christoph Hellwig <hch@infradead.org>
To: Eric Sandeen <sandeen@redhat.com>
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On Fri, Oct 21, 2011 at 10:52:11AM -0500, Eric Sandeen wrote:
> With an SSD, you -really- don't know the independent failure domains,
> with all the garbage collection & remapping that they may do, right?

In fact some popular consumer SSDs do some fairly efficient data
de-duplication which completly runs any metadata redundancy on a single
of these devices void.