btrfs subvolume create /var/lib/libvirt/images/
chown libvirt-qemu:kvm images
chattr +C /var/lib/libvirt/images

create root subvolume

mount /dev/sda1 /tmp/btrfs
btrfs subvolume set-default 5 /tmp/btrfs
cd /tmp/btrfs
btrfs subvolume create @

add “ rootflags=subvol=@ ” to grub kernel options

if update-grub fail check this

btrfs subvolume list -p /

create subvolume sub1

btrfs subvolume create <mnt-point-of-pool-or-subvolume>/sub1

take snapshot (thas is another subvolume)

btrfs subvolume snapshot <subvolume> <snap-path>

delete subvolume or snapshot

btrfs subvolume delete <path>