Comment # 41 on bug 1193019 from Michiya Hagimoto

Repair on host.

btrfs check --repair /dev/zvol/pool/guest/bastion/microos-part2
enabling repair mode
Opening filesystem to check...
Checking filesystem on /dev/zvol/pool/guest/bastion/microos-part2
UUID: b6484f21-0b8b-4109-8150-117bb040b496
[1/7] checking root items
Fixed 0 roots.
[2/7] checking extents
No device size related problem found
[3/7] checking free space tree
cache and super generation don't match, space cache will be invalidated
[4/7] checking fs roots
[5/7] checking only csums items (without verifying data)
[6/7] checking root refs
[7/7] checking quota groups
ERROR: out of memory
ERROR: Loading qgroups from disk: -2
ERROR: failed to check quota groups
found 1599578112 bytes used, error(s) found
total csum bytes: 1458440
total tree bytes: 106135552
total fs tree bytes: 97959936
total extent tree bytes: 5898240
btree space waste bytes: 25762174
file data blocks allocated: 29529686016
 referenced 4831297536
extent buffer leak: start 30818304 len 16384
extent buffer leak: start 58867712 len 16384