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Date: Mon, 8 Nov 2010 21:44:29 +0100
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From: "C. P. Ghost" <cpghost@cordula.ws>
To: Roland Smith <rsmith@xs4all.nl>
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Cc: "Svein Skogen \(Listmail account\)" <svein-listmail@stillbilde.net>,
	freebsd-questions@freebsd.org
Subject: Re: ZFS License and Future
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On Mon, Nov 8, 2010 at 7:38 PM, Roland Smith <rsmith@xs4all.nl> wrote:
> On Mon, Nov 08, 2010 at 05:08:33PM +0100, Svein Skogen (Listmail account) wrote:
>> But it's still not capable of true forward-error-correction. If we are
>> to embark upon creating a new solution, using something that is cheap
>> for "normal cases" but can still be used (albeit more expensively) for
>> error recovery would (imho) be better. Even if that means we get less
>> net storage out of the gross pool (it could perhaps be configurable?)
>
> I'm not sure what you mean by "true forward-error-correction". But if you want
> to make _really sure_ that a spinning disk hasn't mangled the data you should:

Maybe something like Reed-Solomon ECC in different blocks.
Should a data block go bad, it could be rebuilt on-the-fly from
those ECC blocks:

http://en.wikipedia.org/wiki/Reed%E2%80%93Solomon_error_correction
http://www.eccpage.com/

-cpghost.

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