Resizing PVs (was: Installation Impressions)

[Nikolaus Rath]

Sam Sharpe <lists.redhat at samsharpe.net> writes:
> On 5 February 2011 20:53, Nikolaus Rath <Nikolaus at rath.org> wrote:
>> JFTR, unfortunately PVs cannot be made smaller. The whole idea of LVM is
>> to do all the resize operations *within* the containers.
>
> JFTR, unfortunately, you'll need to raise a bug against the  pvresize
> manpage then...
>
> http://linux.die.net/man/8/pvresize
>
> ---
> Shrink the PV on /dev/sda1 prior to shrinking the partition with fdisk
> (ensure that the PV size is appropriate for your intended new
> partition size):
>
> pvresize --setphysicalvolumesize 40G /dev/sda1
> ---
>
> When filing the report, please state why your assertion "for the
> record" is correct over the maintainer's.

You can shrink a PV, but you will loose the extents that are stored in
the space that you have truncated. I don't consider that resizing.

>From the same manpage that you looked up:

,----
| pvresize will refuse to shrink PhysicalVolume if it has allocated
| extents after where its new end would be. In the future, it should
| relocate these elsewhere in the volume group if there is sufficient free
| space, like pvmove does. 
`----

Unfortunately, pvmove can only move extends to other PVs but not to a
different location in the same PV.


Why so aggressive?


   -Nikolaus

-- 
 »Time flies like an arrow, fruit flies like a Banana.«

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