Re: Triple parity and beyond

On 19/11/13 19:12, Piergiorgio Sartor wrote:

On Mon, Nov 18, 2013 at 11:08:59PM +0100, Andrea Mazzoleni wrote:

<snip for brevity>

Hi Andrea,

great job, this was exactly what I was looking for.

Do you know if there is a "fast" way not to correct
errors, but to find them?

In RAID-6 (as per raid6check) there is an easy way
to verify where an HDD has incorrect data.

I think the way to do that is just to generate the parity blocks from
the data blocks, and compare them to the existing parity blocks.

I suspect, for each 2 parity block it should be
possible to find 1 error (and if this is true, then
quad parity is more attractive than triple one).

Furthermore, my second (of first) target would
be something like: http://www.symform.com/blog/tag/raid-96/

Which uses 32 parities (out of 96 "disks").

I believe Andrea's matrix is extensible as long as you have no more than
257 disks in total.  A mere 32 parities should not be a problem :-)

mvh.,

David

Keep going!!!

bye,

pg

quoted

Ciao,
Andrea
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