[linux-lvm] Why is part of a PV not usable?

[Stuart D. Gathman]

On Mon, 26 Jan 2009, Allen, Jack wrote:

>         When I do "vgdisplay -v" or pvdisplay to see the PV, why is part
> of the PV not usable? 
> 
>  --- Physical volume --- 
>   PV Name               /dev/sdd1 
>   VG Name               vg01 
>   PV Size               10.00 GB / not usable 3.98 MB 

Because the PV is divided into Physical Extents (PEs) of a fixed size.
Thus, you may waste up to just short of one PE to gain the flexibility
LVM offers.  Your PV is .02 PE short of 2560 PEs.

-- 
	      Stuart D. Gathman <stuart at bmsi.com>
    Business Management Systems Inc.  Phone: 703 591-0911 Fax: 703 591-6154
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