Re: Triple-parity raid6

[Christoph Dittmann <linux-raid@christoph-d.de>]

On 06/10/2011 10:45 AM, David Brown wrote:
> Making multiple parity syndromes is easy enough mathematically:

Adam Leventhal, who wrote the double parity and triple parity code for 
ZFS, mentioned on his blog [1] that going beyond triple parity poses 
significant challenges if write performance should not suffer.

In particular, it looks like a relevant math paper (originally) had a 
flaw in the claim that quad parity and above can be implemented just 
like triple parity.

I don't know the implementation you were going to use, neither am I 
knowledgeable about multi-parity in general. I only thought it might be 
relevant to add to the current discussion that other people had issues 
with implementing N-parity for N > 3.


Christoph

[1] http://blogs.oracle.com/ahl/entry/triple_parity_raid_z