---- From: "Wulfhorst, Heiner" <heiner.wulfho...@claas.com> -- Sent: 2021-03-26
- 10:42 ----
> Thanks, Roman, you got me back on Track!
>
> I am new to btrfs so I was assuming RAID0 means there is no need for equally
> sized disks.
>
> After `btrfs balance start -dconvert=single -dlimit=10 /' output of `btrfs
> filesystem usage /' now shows:
>
> Overall:
> Device size: 579.51GiB
> Device allocated: 126.99GiB
> Device unallocated: 452.52GiB
> Device missing: 0.00B
> Used: 125.42GiB
> Free (estimated): 452.72GiB (min: 226.46GiB)
> Data ratio: 1.00
> Metadata ratio: 2.00
> Global reserve: 24.05MiB (used: 0.00B)
>
> Data,single: Size:19.00GiB, Used:18.98GiB
> /dev/sdd 19.00GiB
>
> Data,RAID0: Size:105.97GiB, Used:105.79GiB
> /dev/sdb2 36.99GiB
> /dev/sdc 31.99GiB
> /dev/sdd 36.99GiB
>
> Metadata,RAID1: Size:1.00GiB, Used:333.61MiB
> /dev/sdb2 1.00GiB
> /dev/sdd 1.00GiB
>
> System,RAID1: Size:8.00MiB, Used:16.00KiB
> /dev/sdc 8.00MiB
> /dev/sdd 8.00MiB
>
> Unallocated:
> /dev/sdb2 9.52GiB
> /dev/sdc 1.00MiB
> /dev/sdd 443.00GiB
>
>
>
> And finally:
> # df -h
> Filesystem Size Used Avail Use% Mounted on
> devtmpfs 3.9G 8.0K 3.9G 1% /dev
> tmpfs 3.9G 0 3.9G 0% /dev/shm
> tmpfs 3.9G 17M 3.9G 1% /run
> tmpfs 3.9G 0 3.9G 0% /sys/fs/cgroup
> /dev/sdb2 580G 126G 20G 87% /
> /dev/sdb2 580G 126G 20G 87% /.snapshots
> /dev/sdb2 580G 126G 20G 87% /usr/local
> /dev/sdb2 580G 126G 20G 87% /opt
> /dev/sdb2 580G 126G 20G 87% /root
> /dev/sdb2 580G 126G 20G 87% /boot/grub2/i386-pc
> /dev/sdb2 580G 126G 20G 87% /boot/grub2/x86_64-efi
> /dev/sdb2 580G 126G 20G 87% /srv
> /dev/sdb2 580G 126G 20G 87% /var
> /dev/sdb2 580G 126G 20G 87% /tmp
> /dev/sdb2 580G 126G 20G 87% /home
> /dev/sdb2 580G 126G 20G 87% /var/cache
> /dev/sdb1 500M 5.3M 495M 2% /boot/efi
> tmpfs 796M 0 796M 0% /run/user/0
>
> Thanks a lot! I will now read further documentation regarding "btrfs single
> vs RAID*" to understand exactly why and how and also convert remaining space
> to single (it's just a test
> system).
>
> Thanks a lot!
>
> BR,
> Heiner
There is an excellent disk space calculator for Btrfs at
https://www.carfax.org.uk/btrfs-usage/
You can test different disk sizes and RAID profiles to see what actual user
disk space you get.
Regards,
Forza
