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Subject: Re: ext4 features
From: Arjan van de Ven <arjan@infradead.org>
To: Alan Cox <alan@lxorguk.ukuu.org.uk>
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Date: Mon, 03 Jul 2006 23:59:56 +0200
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On Mon, 2006-07-03 at 23:12 +0100, Alan Cox wrote:
> Ar Llu, 2006-07-03 am 23:01 +0200, ysgrifennodd Arjan van de Ven:
> > raid is great for protecting against individual disks or sectors going
> > bad. But raid, especially high performance implementations, do not
> > checksum data or detect corruptions. 
> > 
> > They're different purpose with almost zero overlap in purpose or even
> > goal...
> 
> Same layer though - checksums are really a device mapper type problem
> rather than an fs type problem.

file payload checksums.. I'd agree
filesystem metadata.. there checksums do provide value