Should I choose btrfs or ext4 installing to a HDD?

[TEMPPART]

btrfs seems to have a lot of improvements over ext4 but someone said that it's cow, so it will have fragmentation problem on HDDs. Is this true?

[t42]

https://wiki.archlinux.org/title/btrfs#Defragmentation

[Reddog1]

If you want to use btrfs, all I have to say is, 'Are you feeling lucky'? Your choice if you want to 'live on the edge'.

[ajgringo619]

It really depends on why you want to use BTRFS. I use it extensively; the near-instantaneous snapshots are hard to beat. In fact, the only partition I'm not using BTRFS on is my virtual machine storage (but all the Linux VMs do use BTRFS). If you use Timeshift, you'll be shocked at how fast the snapshots are taken/restored.

@Reddog1 - I see these statements/arguments come up all the time. Are you seeing anything recent that would even hint at "feeling lucky"? BTRFS has been around for a long time; it's not like it was just developed. Or, I could just be the luckiest old geezer alive!

[ajgringo619]

https://wiki.archlinux.org/title/btrfs#Defragmentation

Curious why you posted this link - are you saying that you should defrag BTRFS partitions? I never have - just asking.

[Moonstone Man]

Curious why you posted this link - are you saying that you should defrag BTRFS partitions? I never have - just asking.

Until t42 tells the OP what to make of that link, and whenever people post a solitary link with no reason given or commentary on what points to consider, I always assume that they have nothing to say whatsoever.

[t42]

Curious why you posted this link - are you saying that you should defrag BTRFS partitions? I never have - just asking.

OP question - 'I'm interested in btrfs but not sure about fragmentation' Reply: 'If it even is the case it's manageable'
My answer with a link (and your (unwilling?) elaboration of it) are the only direct answer to the original question in this thread.
This board is noticeable for deviating from the initial questions, usual scenario: Q: how ...? A: don't do it.

[t42]

I always assume that they have nothing to say whatsoever.

That's me exactly, thanks...

[Reddog1]

I actually use btrfs on some of my hosts, the ones where I run a lot of virtual machines. For regular users it will certainly work, but if something happens to go wrong getting help isn't as easy because btrfs is, for now, much less known than ext4. If you don't have a specific reason to use btrfs, use ext4. I give the same advice for disk encryption.

[mikeflan]

Should I choose btrfs or ext4 installing to a HDD?

I'll preface my answer with "I have no direct experience with btrfs. I have never used it".

My answer: Use EXT4. Your incremental snapshot creation times will be less than 2 minutes in most cases. So you are not saving much time. Restoring a snapshot does take 4 minutes or so on EXT4. Maybe even a little more. But again, that is not much time to save. btrfs is too much of an unknown for me.

Is the answer different between an HDD and a SSD? I'm thinking No, but I don't know.

[SimonPeter]

TL; DR
Use ext4 when in doubt.

ext4 is more stable but has lesser features.
btrfs is less stable and has more features.

Losing your important data due to an unstable filesystem is really a bitter experience.

Defragmentation is normally unnecessary (and may even be counterproductive) for most (if not all) cases , if you use a Linux filesystem.

BTW: On linux, I use ext4 (almost exclusively) and I have NEVER defragmented any Linux filesystem (ext4, ext3, ext2, btrfs, xfs)