vgdisplay

[Ricky B. Nino]

Hi,

In the vgdisplay -v /dev/vgXX output. What does the "Total PE" and "Alloc PE" mean? Are the values of these field computed?

regards...

[Christian Gebhardt]

Hi

Total PE: All physical extents you can use for this VG
Alloc PE: All physical extents used for this VG

PE Size (Mbytes): Size of one extent

Chris

[KCS_1]

hi


simply,

Total PE= allocated PE + free PE

Alloc PE= already allocated PE

Free PE = unallocated PE ( Use this PE for allocating)


have a good day!

[Sridhar Bhaskarla · Accepted solution]

Hi,

When you first created the VG, if you didn't specify a value for Physical Extent size, then it would create it with a 4MB extent. An extent is a contiguous set of blocks.

To give you an example, take a 2 GB disk (for easy calculations let's say it's capacity is 2000MB) and configure it under a VG with a default extent size of 4MB. With this, you will get 2000/4=500 extents. If you added another 2GB disk, it would become 1000 extents. This is the "Total PE" in that volume group.

Say you created a logical volume of 400MB. This means you "alloted" 400/4=100 extents to a logical volume. So 100 becomes the "Alloc PE". So, the Alloc PE will be a sum of the extents allocated to all the logical volumes in that VG.

-Sri

[Michael Tully]

Total PE: - Means Total Physical Extents. The extent size is 8mb which means I have 8680*4=34720mb
Allocated is the number which is actually used using the same calculation.

--- Volume groups ---
VG Name /dev/vg00
VG Write Access read/write
VG Status available
Max LV 255
Cur LV 14
Open LV 14
Max PV 16
Cur PV 2
Act PV 2
Max PE per PV 4350
VGDA 4
PE Size (Mbytes) 8
Total PE 8680
Alloc PE 3644
Free PE 5036
Total PVG 0
Total Spare PVs 0
Total Spare PVs in use 0

[T G Manikandan]

You should look at

Total PE
PE size
Alloc PE
Total PE--Total PE in the VG which the sum of the number of physical extents belonging to each available disk in the volume group.


PE size * total PE =size of the volumegroup(total size of the hard disks in the VG)

[Sergejs Svitnevs]

man vgdisplay
Total PE = Alloc PE + Free PE

Total PE: Total number of physical extents within the volume group: the sum of the number of physical extents belonging to each available physical volume in the volume group.
Alloc PE: Number of physical extents currently allocated to logical volumes.
Free PE: Number of physical extents not allocated.

A Physical Extent is a unit used for allocating disk space to logical volumes. The Default size of a physical extent is 4mb.

Regards,
Sergejs