vdev/pool math with combined raidzX vdevs...

[Bob Friesenhahn]

On Wed, 11 Jul 2012, Jason Usher wrote:
>
> I'm not going to beat this to death, but just to summarize, if F is 
> 2, then the corresponding data loss probabilities for RAID-Z1, -Z2, 
> -Z3 are: 14.9%, 1.3%, and 0.086%.

I am not sure what the above percentages mean.

Regardless, I do agree that drive size is a factor in vdev reliability 
(MTTDL).  Huge drives lessen reliability due to increased recovery 
time and placing more data at risk.  There may be a cap on the maximum 
size of "enterprise" drives since "enterprise" drives are normally 
targeted for RAID applications.

Bob
-- 
Bob Friesenhahn
bfriesen at simple.dallas.tx.us, http://www.simplesystems.org/users/bfriesen/
GraphicsMagick Maintainer,    http://www.GraphicsMagick.org/