On Mon, Dec 4, 2023 at 5:07 PM Laura Hild <[log in to unmask]> wrote:
>
> > But shrinking a partition is something that is far less likely to need
> > to be done in an enterprise environment (compared to me fighting with
> > too old hardware at home), so maybe that doesn't really matter.
>
> Especially if you use LVM and leave free space in the VG.  If you're a
> slice-and-dicer and you fully allocate and/or use fixed partitions, then
> using XFS you may come to regret, say, a 10 gig /var and a multi-hundred
> gig root, but if you left root closer to the size it needed to be, you
> just lvextend and xfs_growfs as needed.

No! No. No LVM! Bad admin, no biscuit!

LVM is not a file system, it's partition management scheme, and
encourages *extremely* bad disk management of people attempting to
pre-plot exactly how space every chunk of their OS will take. It
encourages micro-management that can be grotesquely painful to clean
up, especially when you decide to us docker, that run in
/var/lib/docker/, and mock, that lives both in /var/cache/mock/,  and
/var/lib/mock/, and some vendor shoves their database in "/opt/", and
some httpd "build-it-himself" advocate reads the Ubuntu directions and
puts it in "/home/httpd/", and now you have to play whack-a-mole
because some clever person you could make your disk space more
efficient by utting it into *perfectly* sized little bits with LVM.

*Bad* admin. Where's my squirt bottle?

LVM also suffers from the issue when you work from a base OS image and
you try to mount another image of the same reference OS for recovery
purposes, like for example an RHEL or Linux in VMware, the identical
names of the LVM partitions are a nightmare to resolve.

The "I  over-allocated disk" problem has almost nothing to do with
XFS, shrinking ext4 filesystems with resize2fs is usually not worth
the work. It's usually far simpler ot attach another disk and stash
content there for duplication and resizing. I've done this on a grand
scale, back when disks were *much* smaller with dual-disk drive
systems and I could copy to the second disk, about 20,000 systems in
one month.