Re: [PATCH] btrfs: do not zero f_bavail if we have available space

Roman Mamedov
2020-02-19T17:50:55Z

On Wed, 19 Feb 2020 07:36:52 -0800
Marc MERLIN <marc@merlins.org> wrote:

> Thanks. For some reason, debian's latest make-kpkg hangs forever on 5.5
> kernels (not sure why) so I can't build it right now, but I just got
> 5.4.20 and I'm compiling that now, thanks.

Debian deprecates their own tooling for regular users (as opposed to package
mantainers) to easily make custom kernel deb packages[1], they now suggest to
use the kernel-provided "make bindeb-pkg" instead.

[1] https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=925411#17

> As for dm-thin, I'm not sure yet, I'll find out when the new kernel is
> installed. I was also hoping fstrim would work, I guess I'll find out.

Indeed fstrim does deprovision backing storage on thin LVM just fine.

However I am not sure what is the relation with the bug being discussed. The
"zero f_bavail" was just returning "0" to df, while that was not actually
true. Seems puzzling how would that lead to increased usage of dm-thin for you.

--
With respect,
Roman