One of my linux boxes ran out of disk space, which surprised me, because it definitely didn’t have that much stuff on it. When I check with df it says I have used 212GB on my / path:
$ df -h /
Filesystem Size Used Avail Use% Mounted on
/dev/sda1 227G 212G 5.2G 98% /
So, I tried to use du to see if maybe a runaway log file was the cause, but this says I have only used 101GB on my / path (this is also more in-line with how much space I expected to be used):
$ du -h | sort -h
...
101G /
Using those commands with sudo outputs the same sizes.
My filesystem is Btrfs, I’ve tried the suggestion to use btrfs balance start ... but this actually INCREASED my disk usage to 99% lol
So my question is… what on earth is using the remaining 111GB?? Why can I not see it in du?
Interesting, this could be it? I haven’t configured any mounts on this device yet, but when I tried one of the other suggestions from this thread and use
btdu, I get this error:$ ./btdu -x / Fatal error: The mount point you specified, "/", is not the top-level btrfs subvolume ("subvolid=5,subvol=/"). It is the btrfs subvolume "subvolid=256,subvol=/@rootfs". Please specify the path to a mountpoint mounted with subvol=/ or subvolid=5. E.g.: mkdir /mnt/sda1 && mount -o subvol=/ /dev/sda1 /mnt/sda1 && ./btdu /mnt/sda1 Note that the top-level btrfs subvolume ("subvolid=5,subvol=/") is not the same as the root of the filesystem ("/").I’m fairly new to the workings of Btrfs so this is jibberish to me right now, but I’ll look into it more
EDIT: Nevermind! I was just using the tool wrong. I needed to mount my btrfs “sub-volume” then do the scan against that:
sudo mkdir -p /mnt/btdusudo mount -o subvolid=5 /dev/sda1 /mnt/btdusudo ./btdu /mnt/btdu