Does anaconda use sub-volumes by default?

Hello everyone!

I’ve been learning about how btrfs works on a deeper level just to understand my system better, and I noticed all my data is on the top level of the fs. This confused me because when I installed I just did the auto partition option in anaconda. So my question is, is there a specific reason why my home, for example, wasn’t placed in a subvolume by default? Especially given that btrfs is the default on fedora, I would expect it to take advantage of what makes btrfs special.

Thanks!

Are you sure about that?

I’m using the KDE install on an aarch64 VM.

$ sudo btrfs subvolume list /
ID 256 gen 3848 top level 5 path home
ID 257 gen 3848 top level 5 path root

What is the output of the following?

lsblk -f
sudo cat /etc/fstab
sudo btrfs subvolume list /
2 Likes

Ok, thanks.
So sudo btrfs subvolume list / gives me

$ sudo btrfs subv list /
ID 256 gen 344720 top level 5 path home
ID 257 gen 344720 top level 5 path root
ID 258 gen 344643 top level 257 path var/lib/machines

and my fstab says it’s mounting them as subvolumes, but why are they both on the top level? I was watching this video by chris titus tech and in the time stamp in the link you can see that on hist system he has his root subvol on top level 5, and all the others are on level 256. Earlier in the video he reccomends not putting everything on the top level because it makes disk expansion easier. Does that mean that my home and root are on the top level together? Wouldn’t that be a consideration with anaconda or are they assuming that if you’re going to do that kind of disk management you’ll just partition manually at install?

Anaconda is using best practice for btrfs as far as I know.
What do you think you cannot do that you want to do?

In the video subvols root and home are divided into different partitions, while your default fedora installation created the root and home subvols on the same btrfs device (partition).

The top level is ID 5, the subvolumes start at ID 256, etc.
In the video the root subvol has ID 256 with top level (parent) 5 the same as in your fedora setup.

What you are watching is a video optimized for Time-shift. Time-shift is more a Ubuntu thing. This Partition-names starting with @ is what is needed for it.

As fedora does, is using the same hard drive and Yes, i makes by default this sub-volumes. Just not the Ubuntu alias Timeshift way with the “at” @ sighn.

The sub-volumes are on the same physical partition. But as Btrfs allows you to use the same space, it not uses as fix space for a single sub-volume. It uses the space dynamically together.

Have a look to other tutorials where the Youtubers use Fedora and the Btrfs-Assistant. Alias the snapper tool to make snapshots. This way you will probably find more users who can help you.