Btrfs shows incorrect disk size after running a replace command

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I have just recently replaced two 750 GB disks with two 1 TB disks. I used the replace command to do so, aka "btrfs replace start /dev/sdX /dev/sdY /mountpoint". Each replacement went smoothly, with no errors reporting. I'm positive that the source and destination drives were identified correctly. However, when I run "btrfs filesystem show", the output is

Label: none uuid: b2dbc0e4-94fc-4089-9221-d79d7919f8cb

    Total devices 2 FS bytes used 494.23GB
    devid    2 size 698.64GB used 495.03GB path /dev/sda
    devid    1 size 698.64GB used 495.03GB path /dev/sdb

Btrfs v0.20-rc1

The disks show up as the 750 GB, when they are in fact 1 TB. smartctl for each drive shows

root@Lore:/home/kyle# smartctl -i /dev/sda |grep "User Capacity"
User Capacity:    1,000,204,886,016 bytes [1.00 TB]

root@Lore:/home/kyle# smartctl -i /dev/sdb |grep "User Capacity"
User Capacity:    1,000,204,886,016 bytes [1.00 TB]

Is there any harm in this? If it is simply a superficial bug I will not worry. Would running a balance help? As for the specifics, I'm using

Debian testing x64
Vanilla kernel 3.13.0
AMD hardware

Thanks,

Kyle Bentley

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[email protected]
UAB Dept of Physics
1300 University Blvd
CH 310
Birmingham, AL
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Hello Kyle,

you will probably have to tell btrfs to use the complete devices. Checkout "btrfs filesystem resize". There are cases when one does not want to grow the used space on a replacement disk automatically, e.g. when the disk is to be replaced with a smaller disk again, so this is not a bug.

Cheers,
Andreas