From mboxrd@z Thu Jan  1 00:00:00 1970
From: Gilad Arnold <arnold@cs.berkeley.edu>
Subject: Re: migrating from RAID5 to RAID10
Date: Thu, 10 Jun 2010 15:30:48 -0700
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To: Drew <drew.kay@gmail.com>
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On Thu, Jun 10, 2010 at 03:21:27PM -0700, Drew wrote:
> In this case, you're parity blocks will actually be identical to your
> non-parity blocks. This is because P1 is calculated as P1 = A1 XOR ??
> Since there is no other block to XOR your bits with, md falls back to
> ?? = 0, and we all know that the XOR of 0 is the identity. That is, P1
> = A1 XOR 0 == A1

I'm curious whether md actually computes the XOR or has a shortcut path
for the case where n=2.

> I stand corrected. :-)

No problem ;-)

Gilad