On my 256 GB disc:# btrfs fi show /dev/sdd3Total devices 1 FS bytes used 143.43GiBdevid    1 size 234.22GiB used 234.22GiB path /dev/sdd3Btrfs v3.12I don't understand the discrepancy between 143.43GiB and used 234.22GiB. I thought, perhaps I have duplication of the data on, but the way I read this:# btrfs filesystem df /Data, single: total=230.20GiB, used=142.32GiBSystem, DUP: total=8.00MiB, used=32.00KiBSystem, single: total=4.00MiB, used=0.00Metadata, DUP: total=2.00GiB, used=1.19GiBMetadata, single: total=8.00MiB, used=0.00my data is stored only once, single, and I don't understand where the remaining, roughtly 100 GiB, is used. Quote from the the btrfs wiki: single - data usage matches the raw block group usage on a single device (data = raw; 1GB of data requires 1GB of diskMount info:# mount | grep sdd3/dev/sdd3 on / type btrfs (rw,noatime,ssd,noacl,space_cache)
Understanding btrfs disc usage for single data volume
btrfs