Re: Btrfs progs release 3.18

On Tue, Dec 30, 2014 at 10:38:38PM +0100, Tomasz Chmielewski wrote:

quoted

* filesystem usage - give an overview of fs usage in a way (道,
みち, michi) that's more
* device usage - more detailed information about per-device allocations
 * same restrictions as for 'fi usage'

Interesting.

Used these to create a filesystem, with btrfs-progs v3.17.3:

# mkfs.btrfs -O skinny-metadata -d raid1 -m raid1 /dev/sda4 /dev/sdb4 -f


Now, with btrfs-progs 3.18 and these new options I can see that the
fs is partially single, not RAID-1 - how come?

   It's always been like that with a new FS. The small single chunks
are part of the way that mkfs works, and will go away on the first
balance operation. It's harmless, and can safely be ignored.

   Hugo.

# btrfs fil us /srv
Overall:
    Device size:                   5.25TiB
    Device allocated:            510.04GiB
    Device unallocated:            4.76TiB
    Used:                        505.39GiB
    Free (estimated):              2.38TiB      (min: 2.38TiB)
    Data ratio:                       2.00
    Metadata ratio:                   2.00
    Global reserve:              512.00MiB      (used: 0.00B)

Data,single: Size:8.00MiB, Used:0.00B
   /dev/sda4       8.00MiB

Data,RAID1: Size:252.00GiB, Used:250.56GiB
   /dev/sda4     252.00GiB
   /dev/sdb4     252.00GiB

Metadata,single: Size:8.00MiB, Used:0.00B
   /dev/sda4       8.00MiB

Metadata,RAID1: Size:3.00GiB, Used:2.13GiB
   /dev/sda4       3.00GiB
   /dev/sdb4       3.00GiB

System,single: Size:4.00MiB, Used:0.00B
   /dev/sda4       4.00MiB

System,RAID1: Size:8.00MiB, Used:64.00KiB
   /dev/sda4       8.00MiB
   /dev/sdb4       8.00MiB

Unallocated:
   /dev/sda4       2.38TiB
   /dev/sdb4       2.38TiB


root@backup01 ~ # btrfs dev us /srv
/dev/sda4, ID: 1
   Device size:             2.63TiB
   Data,single:             8.00MiB
   Data,RAID1:            252.00GiB
   Metadata,single:         8.00MiB
   Metadata,RAID1:          3.00GiB
   System,single:           4.00MiB
   System,RAID1:            8.00MiB
   Unallocated:             2.38TiB

/dev/sdb4, ID: 2
   Device size:             2.63TiB
   Data,RAID1:            252.00GiB
   Metadata,RAID1:          3.00GiB
   System,RAID1:            8.00MiB
   Unallocated:             2.38TiB

-- 
Hugo Mills             | The trouble with you, Ibid, is you think you know
hugo@... carfax.org.uk | everything.
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