On Wed, Feb 26, 2020 at 7:45 AM Leszek Dubiel <leszek@xxxxxxxxx> wrote: > > > Added /dev/sdb3, /dev/sdd3 and /dev/sdf3 to btrfs filesystem: > > > Label: none uuid: 44803366-3981-4ebb-853b-6c991380c8a6 > Total devices 6 FS bytes used 8.20TiB > devid 2 size 5.45TiB used 4.36TiB path /dev/sda2 > devid 3 size 5.45TiB used 4.36TiB path /dev/sdc2 > devid 4 size 10.90TiB used 8.71TiB path /dev/sde3 > devid 5 size 9.06TiB used 0.00B path /dev/sdb3 <<< > devid 6 size 5.43TiB used 0.00B path /dev/sdd3 <<<< > devid 7 size 3.61TiB used 0.00B path /dev/sdf3 <<<< > > > > Filessytem df looks good 20T of filesystem: > > root@wawel:~# df -h / > Filesystem Size Used Avail Use% Mounted on > /dev/sda2 20T 8.3T 9.2T 48% / > > > > But disks seem to be NOT used by btrfs: > > root@wawel:~# btrfs dev usag / > /dev/sda2, ID: 2 > Device size: 5.45TiB > Device slack: 0.00B > Data,RAID1: 4.28TiB > Metadata,RAID1: 89.00GiB > Unallocated: 1.09TiB > > /dev/sdb3, ID: 5 > Device size: 9.06TiB <<<< no data usage? > Device slack: 3.50KiB > Unallocated: 9.06TiB > > /dev/sdc2, ID: 3 > Device size: 5.45TiB > Device slack: 0.00B > Data,RAID1: 4.28TiB > Metadata,RAID1: 83.00GiB > System,RAID1: 32.00MiB > Unallocated: 1.09TiB > > /dev/sdd3, ID: 6 > Device size: 5.43TiB <<<<<<<<???? > Device slack: 3.50KiB > Unallocated: 5.43TiB > > /dev/sde3, ID: 4 > Device size: 10.90TiB > Device slack: 3.50KiB > Data,RAID1: 8.55TiB > Metadata,RAID1: 162.00GiB > System,RAID1: 32.00MiB > Unallocated: 2.19TiB > > /dev/sdf3, ID: 7 > Device size: 3.61TiB <???? > Device slack: 3.50KiB > Unallocated: 3.61TiB > > > > Newly added disks seemed not to be used... So I've done: > > btrfs balance start -dconvert=raid1,soft -mconvert=raid1,soft / > > > It didn't help. So I used: > > > > root@wawel:~# btrfs balance start -dusage=0 -musage=0 / > Done, had to relocate 0 out of 9050 chunks > > > then: > > > root@wawel:~# btrfs balance start -dusage=1 -musage=1 / > Done, had to relocate 106 out of 9050 chunks > > > > And I still don't see any usage of the devices... > > > Shall I activate these newly added block devices somehow? > Those 106 reallocated chunks should have been put to new devices, right? Only if you do a full balance. It's not strictly necessary, and may not be advantageous, but that depends on the workload. As you start writing, eventually Btrfs will allocate a new raid1 block group, and it will pick the devices that have the most free space. That suggests /dev/sde3 and /dev/sdb3. They'll be used for quite a while, until one or two other disks have the most free space remaining, and then they'll accept the writes. So you can let Btrfs balance them lazy style by doing nothing. Or you can do a full balance to balance them now, which might take ~50 hours depending on the performance of the drives. -- Chris Murphy
