According to the archwiki article on a swapfile on btrfs: https://wiki.archlinux.org/title/Btrfs#Swap_file
Tip: Consider creating the subvolume directly below the top-level subvolume, e.g. @swap. Then, make sure the subvolume is mounted to /swap (or any other accessible location).
But… why? I’ve been researching for a bit now, and I still don’t understand the benefit of a subvolume directly below the top level subvolume, as opposed to a nested subvolume.
At first I thought this might be because nested subvolumes are included in snapshots, but that doesn’t seem to be the case, according to a reddit post… but I can’t find anything about this on the arch wiki, gentoo wiki, or the btrfs readthedocs page.
Any ideas? I feel like the tip wouldn’t just be there just because.
Yeah, I read that manual but it didn’t answer my question.
The big problem is that the arch wiki describes a setup with nested subvolumes first (in a subvolume below @ or whatever your root subvolume is), but then suggests in a tip to use a subvolume directly below the top level subvolume. The limitations mentioned in that manual don’t seem to apply to either setup, as they would prevent swap from working, which is not the case. I have tested both setups and they work fine — or so it seems. I’m worried there is some hidden gotcha I’m missing.
in addition to that, some of those limitations simply don’t apply to my setup, as I only have a single device.