BTRFS raid filesystem

:~# btrfs fi show
Label: none  uuid: 711ddb53-318b-43d6-91cd-b18c8983e886
	Total devices 2 FS bytes used 3.34GiB
	devid    1 size 46.57GiB used 6.03GiB path /dev/sda3
	devid    2 size 46.57GiB used 6.03GiB path /dev/sdb3

Label: none  uuid: 00c63666-d63d-4c08-8d18-81b1c33bbef7
	Total devices 2 FS bytes used 113.27MiB
	devid    1 size 1.86GiB used 672.00MiB path /dev/sda1
	devid    2 size 1.86GiB used 672.00MiB path /dev/sdb1

Label: none  uuid: 508358ca-5cbe-47db-befb-3656307883ea
	Total devices 2 FS bytes used 435.65GiB
	devid    1 size 1.77TiB used 437.06GiB path /dev/sda4
	devid    2 size 1.77TiB used 437.06GiB path /dev/sdb4