Andy Smith [off-list ref] wrote:

On Wed, Dec 21, 2005 at 12:55:47PM +1100, Christopher Smith wrote:

quoted

Why would you use RAID6 and not RAID10 with four disks ?

I was wondering the same thing.  It's true that RAID6 is guaranteed
to still run degraded after losing 2 devices, whereas a RAID10 on 4
devices could only lose 1 device from each RAID1.  So there is some
small extra redundancy there.

That's the reason - better reliability.  With 4-disk RAID-10, a 2-disk
failure has a 1/3 chance of causing array failure.  With RAID-6, there
is no chance.

But how does the performance for read and write compare?

Good question!  I'll post some performance numbers of the RAID-6
configuration when I have it up and running.


-- 
Sebastian Kuzminsky