[lustre-discuss] When ZFS MDT becomes full, statfs will show an overflow value(2YiB)

[Homer Li]

 Hi All,
     Lustre ver; 2.15.7, ZFS 2.2.7, The KVM virtual MDS host
     If you continue creating files until the client indicates "No
space left on device", df shows 2 YiB capacity.
    Thanks

=======
df -t lustre
Filesystem                       1K-blocks                   Used
Available Use% Mounted on
test_mdt0/test_mdt0              240131200              240131200
   0 100% /test_lustre/test_mdt0
test_mdt0/test_mgt0 2361183241434822593280 2361183241434822593280
   0 100% /test_lustre/test_mgt0

zfs set quota=50G test_mdt0/test_mgt0
df -h -t lustre
Filesystem           Size  Used Avail Use% Mounted on
test_mdt0/test_mgt0  2.0Y  2.0Y     0 100% /test_lustre/test_mgt0

zpool list
NAME        SIZE  ALLOC   FREE  CKPOINT  EXPANDSZ   FRAG    CAP  DEDUP
   HEALTH  ALTROOT
test_mdt0   238G   231G  7.40G        -         -    97%    96%  1.00x
   ONLINE  -

 zpool status
  pool: test_mdt0
 state: ONLINE
config:

NAME        STATE     READ WRITE CKSUM
test_mdt0   ONLINE       0     0     0
  sda       ONLINE       0     0     0
  sde       ONLINE       0     0     0
  sdf       ONLINE       0     0     0

errors: No known data errors

lsscsi -gis | grep -E 'sda|sde|sdf'
[0:0:0:0]    disk    QEMU     QEMU HARDDISK    2.5+  /dev/sda
SQEMU_QEMU_HARDDISK_0000  /dev/sg0   85.8GB
[0:0:0:1]    disk    QEMU     QEMU HARDDISK    2.5+  /dev/sdf
SQEMU_QEMU_HARDDISK_0001  /dev/sg5   85.8GB
[0:0:0:2]    disk    QEMU     QEMU HARDDISK    2.5+  /dev/sde
SQEMU_QEMU_HARDDISK_0002  /dev/sg4   85.8GB

=======

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