unexpected raid1 behavior?

Jean-Philippe Robichaud
2009-11-27T20:41:17Z

Hi, I'm starting to play with btrfs on my new computer. I'm running Gentoo and
have compiled the 2.6.31 kernel, enabling btrfs.

Now I have 2 partitions (on 2 different sata disks) that are free for me to
play with, each about 375 gb in size. I wanted to create a "raid1" volume
using these two partitions, so I did:

# mkfs.btrfs -d raid1 /dev/sda5 /dev/sdb5
# mount /dev/sda5 /btrfs

and everything seems fine.

Now what I find strange is that everything looks like a raid0 was created, not
a raid1:

$ df -h /btrfs/
Filesystem Size Used Avail Use% Mounted on
/dev/sda5 684G 72G 612G 11% /btrfs

What am I doing (or understanding) wrong?

Thanks!

Jp