"Michael VanLoon" writes:
> RAID-5 doesn't give you high performance.  I think to get high
> performance *and* high reliability, you need to forget about parity, and
> do normal RAID-0 striping on top of pairs of RAID-1 mirrored drives.
> This gives you full ccd-like striped write performance, and double read
> performance since it can interleave reads to between the mirrored
> drives.

[snip: RAID 0 over multiple RAID 1's]

> It's kind-of expensive, since you have to have two physical drives for
> each logical drive.  But it gives you the highest reliability, with the
> fastest fail-over, and the highest performance, all at the same time.
> Just my theory anyway, I can't afford enough drives to try this (and I'm
> not sure which RAID solutions even support striping on top of multiple
> mirrors).

RAIDframe should be able to handle it, although I've not tested it... 
(RAID 0 over two RAID 5's works fine...)

Later...

Greg Oster

oster@cs.usask.ca
Department of Computer Science
University of Saskatchewan, Saskatoon, Saskatchewan, CANADA