LVM and 4K sectors

[Benny Siegert <bsiegert%netbsd.org@localhost>]

I am trying to set up LVM on a 4T hard drive that has 4096-byte
sectors. However:

# gpt create sd0
# gpt add  sd0
/dev/rsd0: Partition 1 added: 49f48d5a-b10e-11dc-b99b-0019d1879648 6 976754635
# newfs /dev/rdk4
/dev/rdk4: 3815447.8MB (976754635 sectors) block size 32768, fragment size 4096
        using 5148 cylinder groups of 741.25MB, 23720 blks, 47104 inodes.
super-block backups (for fsck_ffs -b #) at:
8, 189768, 379528, 569288, 759048, 948808, 1138568, 1328328, 1518088,
1707848, 1897608,
^C
#
# gpt type -i 1 -T linux-lvm sd0
/dev/rsd0: Partition 1 type changed
# lvm pvcreate -v -Z y /dev/rdk4
    Set up physical volume for "/dev/rdk4" with 976754635 available sectors
    Zeroing start of device /dev/rdk4
  Physical volume "/dev/rdk4" successfully created
# lvm pvs
  PV         VG   Fmt  Attr PSize   PFree
  /dev/rdk4       lvm2 --   465.75g 465.75g
  /dev/rsd1a vg0  lvm2 a-   931.51g 100.20g

The number of sectors is correct but it assumes that they are 512 bytes.

# lvm pvremove /dev/rdk4
  Labels on physical volume "/dev/rdk4" successfully wiped
# lvm pvcreate -v -Z y --setphysicalvolumesize 3726g /dev/rdk4
  WARNING: /dev/rdk4: Overriding real size. You could lose data.
    /dev/rdk4: Pretending size is 7813988352 sectors.
    Set up physical volume for "/dev/rdk4" with 7813988352 available sectors
    Zeroing start of device /dev/rdk4
  Physical volume "/dev/rdk4" successfully created
# lvm pvs
  PV         VG   Fmt  Attr PSize   PFree
  /dev/rdk4       lvm2 --     3.64t   3.64t
  /dev/rsd1a vg0  lvm2 a-   931.51g 100.20g

How safe will my data be on this? Is it a terrible idea to mix two
disks in a VG if one of them has 512-byte sectors and one 4K sectors?

-- 
Benny