ZFS: root pool considerations, multiple pools on the same disk

[Hugo Silva]

Hello,

I've been doing some tests with 9.0 RC3 and ZFS. This particular server
has 6 disks and a single zpool on mfid?p3 partitions, which I've
temporarily arranged into a raid-10 with 2 spares, single pool.


I've been thinking about whether it makes sense to separate the rpool
from the data pool(s)..

It seems to make sense at some levels to separate the rpool from the
app/user data, but to me it's less clear whether this is a good idea or
not when the backing disks are all the same.

One idea would be creating a 4-way mirror on small partitions for the
rpool (sturdier), and a zfs raid-10 on the remaining larger partition.

I'm curious about the performance implications (if any) of having >1
zpools on the same disks (considering that during normal usage, it'll be
the data pool seeing 99.999% of the action) and whether anyone has
thought the same and/or applied this concept in production.

Regards,

Hugo