LVM Version 2.0 Volume Groups in HP-UX 11i v3 (September 2008)

2.x can leave as much space for user data on disk as 1.0
For an equivalent provisioning (same extent size and same maximum volume group size), the size of the metadata
on disk is larger for 2.x compared to 1.0. That is because the metadata is provisioned for more logical volumes,
physical volumes, more extents per logical volume (or physical volume), and contains additional information such
as the volume names.
However, because of the different structures of the 2.x metadata, 2.x can leave as much space for user data as
1.0.
2.x volume groups use the space at the end of the disk that cannot be used for user data. Often, the end of the
last extent does not coincide with the end of the disk. 2.x volume groups try to use this left over space between the
end of the last extent and the end of the disk to store metadata. As a consequence, even if the on disk 2.x
metadata is bigger, the space available on disk for user data can be as large for 2.x compared to 1.0.
Example
A 1.0 volume group (vgtestl1) and a 2.0 volume group (vgtestl2) are created with the same provisioning (64 MB
extent and maximum volume group size of 128 TB). They are created on disks of identical size to simplify the
comparison. While the metadata of the 2.0 volume group is bigger, the space available for user data in each
volume group is the same: 2050 extents (from pvdisplay output).
# diskinfo /dev/rdisk/disk148
SCSI describe of /dev/rdisk/disk148:
vendor: COMPAQ
product id: MSA1000 VOLUME
type: direct access
size: 134399790 Kbytes
bytes per sector: 512
# diskinfo /dev/rdisk/disk149
SCSI describe of /dev/rdisk/disk149:
vendor: COMPAQ
product id: MSA1000 VOLUME
type: direct access
size: 134399790 Kbytes
bytes per sector: 512
# vgcreate -V 1.0 -e 16384 -l 255 -p 128 -s 64 vgtestl1 /dev/disk/disk148
(16384*128*64MB = 128TB)
# vgcreate -V 2.0 -s 64 -S 128t vgtestl2 /dev/disk/disk149
# pvdisplay /dev/disk/disk148
--- Physical volumes ---
PV Name /dev/disk/disk148
VG Name /dev/vgtestl1
PV Status available
Allocatable yes
VGDA 2
Cur LV 0
PE Size (Mbytes) 64
Total PE 2050
# pvdisplay /dev/disk/disk149
--- Physical volumes ---
PV Name /dev/disk/disk149
18