Re: btrfs filled up dm-thin and df%: shows 8.4TB of data used when I'm only using 10% of that.

Marc MERLIN
2020-02-22T14:51:44Z

On Fri, Feb 21, 2020 at 05:23:12PM -0800, Marc MERLIN wrote:
> On Fri, Feb 21, 2020 at 05:06:37PM -0800, Marc MERLIN wrote:
> > You asked for a check, it's running but may take a while:
> > gargamel:~# btrfs check /dev/mapper/vgds2-ubuntu
> > Checking filesystem on /dev/mapper/vgds2-ubuntu
> > UUID: 905c90db-8081-4071-9c79-57328b8ac0d5
> > checking extents
> > checking free space cache
> > checking fs roots
> > checking only csum items (without verifying data)
> >
> > I'll paste the completion when it's done.
>
> Ok, faster than I thought. btrfs check came back clean
> I added spaces for readability.
> So this claims I'm using 9TB?
>
> Is it possible that I'm hitting this problem
> 1) I did really fill the filesystem (well not to the filesystem size but
> to the size that dm-thin was not able to give blocks anymore)
> 2) I deleted/freed up the space
> 3) btrfs needs space to free up the space, and there is no space left,
> so it's unable to mark the free blocks, as free, and I'm therefore
> stuck?
>
> found 9 255 703 285 760 bytes used, no error found
> total csum bytes: 9 019 442 564
> total tree bytes: 17 533 894 656
> total fs tree bytes: 7 411 073 024
> total extent tree bytes: 379 928 576
> btree space waste bytes: 1 769 834 145
> file data blocks allocated: 9267682025472
> referenced 9272533270528

Ok, last call before I delete this filesystem and recover my system to a
working state. I don't need the filesystem fixed, it's fairly quick for
me restore it, but obviously if there is any useful state in it for
improving the code, that will be lost.

I understand it's the weekend, if someone thinks I should wait until
monday to give some other folks the chance to see/reply, let me know,
and I'll keep my system down until monday.

Marc
--
"A mouse is a device used to point at the xterm you want to type in" - A.S.R.

Home page: http://marc.merlins.org/ | PGP 7F55D5F27AAF9D08