Re: BTRF: no free space

[Roman Mamedov <rm@romanrm.net>]

On Sun, 22 Oct 2023 17:40:05 +0200
Reindl Harald <h.reindl@thelounge.net> wrote:

> >> [root@arrakisvm:~]$ btrfs fi df /mnt/fileserver-backup
> >> Data, single: total=1.95TiB, used=207.05GiB
> >> System, DUP: total=8.00MiB, used=224.00KiB
> >> Metadata, DUP: total=1.00GiB, used=945.61MiB
> >> GlobalReserve, single: total=512.00MiB, used=0.00B
> > 
> > 1) Report your kernel version
> 
> 6.5.7-100.fc37.x86_64
> 
> > 2) Retry without "ssd" and especially without "ssd_spread". The weird thing
> > here is that it appears the FS has allocated the entire unused space as "data"
> > chunks, leaving no space for any new metadata chunk. Personally I don't have
> > any other guess for the cause aside from the rarely-used (and little-tested?)
> > ssd_spread option. Of course still a bug even if so.
> 
> no - it allocated METADATA
> Metadata, DUP: total=1.00GiB, used=945.61MiB

In your output I see that 1.95 TB was allocated for data chunks, even if only
207 GB of those are used for actual data. My guess was that this was
preventing the creation of one more metadata chunk when it was needed, which
broke everything.


-- 
With respect,
Roman