I tried to swap out a btrfs with a lager disk. The idea was to add the new disk and remove the old one. So I added to the original 4TB disk with about 3TB data a new 5TB disk and started the btrfs remove of the old disk. I ended with btrfs ERROR: error removing device: No space left on deviceSo I tried to re balance made more space. Including with the dusage parameter like here. I even tried removing the new device. I always get No space left. The array is not even close to full, there is enough space on ether disk left for all data. I also tried multiple kernels including 4.8 and 4.4.btrfs fi sh /mnt/backup/Label: 'Backup'  uuid: 045f75c3-fe26-436d-b2ff-c84b70c60eebTotal devices 2 FS bytes used 2.56TiBdevid    1 size 3.64TiB used 2.58TiB path /dev/md127p1devid    2 size 4.55TiB used 339.00GiB path /dev/sddbtrfs fi df /mnt/backup/Data, RAID0: total=678.00GiB, used=677.91GiBData, single: total=2.25TiB, used=1.89TiBSystem, single: total=32.00MiB, used=316.00KiBMetadata, single: total=4.00GiB, used=3.19GiBGlobalReserve, single: total=512.00MiB, used=0.00BIs there something left I can try? 
btrfs ERROR: error removing device: No space left on device
disk usage;btrfs