Posted a while back about this and got no useful reply. Please help a guy out regarding his computer:
sudo btrfs fi usage /media/user/btrfs
Overall:
Device size: 14.55TiB
Device allocated: 8.32TiB
Device unallocated: 6.23TiB
Device missing: 0.00B
Used: 8.26TiB
Free (estimated): 3.15TiB (min: 3.15TiB)
Data ratio: 2.00
Metadata ratio: 2.00
Global reserve: 512.00MiB (used: 0.00B)
Data,RAID10: Size:4.15TiB, Used:4.12TiB (99.26%)
/dev/sda 2.08TiB
/dev/sdb 2.08TiB
/dev/sdc 2.08TiB
/dev/sdd 2.08TiB
Metadata,RAID10: Size:10.00GiB, Used:8.32GiB (83.17%)
/dev/sda 5.00GiB
/dev/sdb 5.00GiB
/dev/sdc 5.00GiB
/dev/sdd 5.00GiB
System,RAID10: Size:128.00MiB, Used:464.00KiB (0.35%)
/dev/sda 64.00MiB
/dev/sdb 64.00MiB
/dev/sdc 64.00MiB
/dev/sdd 64.00MiB
Unallocated:
/dev/sda 1.56TiB
/dev/sdb 1.56TiB
/dev/sdc 1.56TiB
/dev/sdd 1.56TiB
btrfs fi df /media/user/btrfs
Data, RAID10: total=4.15TiB, used=4.12TiB
System, RAID10: total=128.00MiB, used=464.00KiB
Metadata, RAID10: total=10.00GiB, used=8.32GiB
GlobalReserve, single: total=512.00MiB, used=0.00B
Some say I should rather store all metadata as RAID1 since it barely takes up space and the redundancy protects in case of a 2 drive failure. Do you recommend me doing so and can I simply rebalance with
btrfs balance start -mconvert=raid1 /media/user/btrfs
?
Also it is obvious there is 4x4TB = 16 TB installed. I would expect 8 TB of space. Is it correct that the discrepancy here between my expectation and the above reports is due to BTRFS allocating space as it is needed ? So if I now chose to dd 3 TB into a file on the drive it would start allocating the 3TiB dynamically ?
Thanks.