Btrfs commands

btrfs filesystem show
btrfs filesystem df /run/media/lucifer/SD_BTRFS
btrfs device stats /run/media/lucifer/SD_BTRFS
btrfs subvolume show /run/media/lucifer/SD_BTRFS
btrfs scrub start -B -d /run/media/lucifer/SD_BTRFS
btrfs scrub status -d /run/media/lucifer/SD_BTRFS

btrfs check --check-data-csum --clear-space-cache v1 -p --repair /dev/sdh
btrfs device add /dev/sdc /run/media/lucifer/SD_BTRFS
btrfs balance start /run/media/lucifer/SD_BTRFS

btrfs fi usage /run/media/lucifer/SD_BTRFS

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find errors on partition:
sudo find /run/media/lucifer/SD_BTRFS -type f -exec cp {} /dev/null 2>&1 \; | tee /home/lucifer/SD_BTRFS_errors.txt