On Mon, May 02, 2022 at 05:46:42PM +0200, Steinar H. Gunderson wrote: > On Mon, May 02, 2022 at 05:23:08PM +0200, Julian Andres Klode wrote: > > plocate considers all mount points of a btrfs as bind mounts, > > so when I have a somewhat usual case of subvolumes, e.g. > > Hi, > > It considers them as bind mounts because btrfs implements subvolumes > as bind mounts. This is documented in updatedb.conf(5) (which refers to > btrfs-subvolume(8) and shows a workaround), so I'm closing this.
It says to make / as subvolume as well, which seems incomplete, as mounted at / is the subvolume @ (that's the standard Ubuntu layout); the actual non-subvolume / is only mounted at /mnt for managing snapshots (later /var/lib/apt-btrfs-snapshot). updatedb needs to parse /proc/mounts, look for subvol= flag, and for each subvol= traverse the shortest path (or first path it sees). Essentially this is broken for btrfs users now unless they only mount once. Which doesn't *always* work for various reasons, e.g. if you want to snapshot / but not /var/log, you have to have them be subvolumes /@ and /@log such that you backup the former. If you had / and /var/log were a direct subvolume, you'd lose it on restore. -- debian developer - deb.li/jak | jak-linux.org - free software dev ubuntu core developer i speak de, en