I've ascertained that ZFS appears to be able to correctly determine native
sector size. On a Xen DomU I get:
# zdb | grep ashift
ashift: 9
On a physical machine with a disk with 4k native sectors I get:
# zdb | grep ashift
ashift: 12
However, I cannot see a way to override this when creating a pool. The
options seen in wider ZFS documentation are missing:
# zpool get all | grep ashift
#
# zpool create -o ashift=12 tank xbd1d
property 'ashift' is not a valid pool property
#
No vfs.zfs.min_auto_ashift sysctl:
# sysctl vfs.zfs
vfs.zfs.version.ioctl = 7
vfs.zfs.version.spa = 5000
#
--
Stephen
