Experiences with LVM vs btrfs

[Petter Adsen]

On Wed, 29 Apr 2015 00:28:41 -0400
"Andrew J. Caines" <Ubuntu at halplant.com> wrote:

> Petter,
> 
> > The system is on two 250G drives in RAID1 (now mdadm, xfs), and I
> > specifically want snapshots, subvolumes would also be nice. What I
> >  would like to know, is: should I put LVM on top of the RAID, or
> > should I dispense of mdadm altogether and let btrfs take care of
> > everything?
> 
> Which did you choose and what have you experienced so far?

I went with LVM and mdadm, since that is closest to what I already
know, and very mature. So far I'm really happy with it, it's was really
easy to set up and has a lot of nice features.

At home I run a few things in VMs and using LVM for storage improves on
performance.

Still wanting to play with btrfs, I've ordered two 1T drives so I can
test it out before committing to it on data I care about.

> My 12.04 desktop used md for the three 1 TB disk RAID 5 and has been
> faultless in the 4.5 years it has run [I say with no sense of hubris].
> The btrfs v0.19 on it has also behaved well, though I've not used any
> interesting features.
> 
> My media PC runs 14.04 and uses a btrfs v3.12 RAID 1 across two 1 TB
> disks with subvolumes and apart from causing a little confusion to
> gnome-disks about what's on what disk*, it has also run flawlessly for
> maybe a year since being built. I've not played with snapshots.
> 
> The various btrfs docs are still full of overly conservative warnings,
> but in my experience the basic functionality is solid and I have no
> lost any data to the filesystem - something I cannot say of the ext
> family.

Well, I can't honestly remember when I last lost data on an ext*
filesystem, but I stayed with xfs as shrinking LV's is rarely done.
It's just as easy (and probably faster) to move the data, resize, and
move the data back.

> > Can someone who has experience with LVM and/or btrfs give me some
> > advice on what is the best to work with, easiest to learn, requires
> >  little maintenance, etc?
> 
> Start with btrfs since it's both volume manager and filesystem,

Well, I didn't :)

> inspired by the widely-deployed-in-the-real-world ZFS and reasonably
> mature. You are already doing it right by having working backups and
> reasonable expectations of performance.

I've been using computers since I was 5, so I've learnt the value of
backups a few times :)

> > What would the experts out there recommend to someone who is new
> > to both?
> 
> No idea, but interested to find out. What did they say?

The responses I got was mostly to stick to what I knew the most about,
which was mdadm and LVM. Good advice :)

Petter

-- 
"I'm ionized"
"Are you sure?"
"I'm positive."
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 213 bytes
Desc: OpenPGP digital signature
URL: <https://lists.ubuntu.com/archives/ubuntu-users/attachments/20150429/589b3c30/attachment.sig>