Re: RAID 5 vs RAID 10 benchmark

Jonathan Lewis wrote:
> I thought Hamming codes were a little sophisticated -
> whereas Raid-5 parity simply does an XOR across
> the data blocks to generate the parity block. That
> way ANY one block is equivalent to the XOR
> across all the other blocks in same stripe, which
> is why you can reconstruct any failed block if
> you have all but one of the blocks in the stripe.
>

Hmmmm, looks like my reply to you never made it... It read something like:
Looks like you are correct about this, but how is data reconstructed then? Mind you - a missing disk, as well as a data error should be corrected, if it just happens to be.

I misread RAID-2 (using Hamming codes for ECC) as the *lowest* version to use Hamming codes. This is not the case - it appears to be the *only* configuration using (s/w) ECC.

-- 
Regards,
Frank van Bortel