why does the space usage for a pool percentage differ from what df or Windows think?

[tkimnguyen]

We got a warning,

Code:

Space usage for pool "TriangleBackups" is 88%. Optimal pool performance requires used space remain below 80%

but Windows reports 9.97 TB used (19.5 TB free) out of 29.4 TB (i.e., 33.9% used).

How can I tell what is using up the additional space?

What can I do to free up what the NAS thinks is taking up all that space?

Code:

# zpool list
NAME              SIZE  ALLOC   FREE  CKPOINT  EXPANDSZ   FRAG    CAP  DEDUP    HEALTH  ALTROOT
SSD_Spare         109G  1.71M   109G        -         -     0%     0%  1.00x    ONLINE  /mnt
TriangleBackups  43.5T  38.3T  5.18T        -         -    29%    88%  1.00x    ONLINE  /mnt
freenas-boot     14.9G  8.67G  6.20G        -         -      -    58%  1.00x    ONLINE  -

# zfs list
NAME                                                               USED  AVAIL     REFER  MOUNTPOINT
SSD_Spare                                                         1.71M   106G       88K  /mnt/SSD_Spare
TriangleBackups                                                   29.7T   977G      188K  /mnt/TriangleBackups
TriangleBackups/.system                                            259M   977G      239K  legacy
TriangleBackups/.system/configs-a421eaccddb44c098d96b72146b5211d   217M   977G      217M  legacy
TriangleBackups/.system/cores                                      188K  1024M      188K  legacy
TriangleBackups/.system/rrd-a421eaccddb44c098d96b72146b5211d      39.5M   977G     39.5M  legacy
TriangleBackups/.system/samba4                                    1.30M   977G      589K  legacy
TriangleBackups/.system/services                                   205K   977G      205K  legacy
TriangleBackups/.system/syslog-a421eaccddb44c098d96b72146b5211d    188K   977G      188K  legacy
TriangleBackups/.system/webui                                      188K   977G      188K  legacy
TriangleBackups/TriangleBackup                                    29.7T  3.44T     27.2T  -
TriangleBackups/iocage                                            17.1M   977G     16.0M  /mnt/TriangleBackups/iocage
TriangleBackups/iocage/download                                    188K   977G      188K  /mnt/TriangleBackups/iocage/download
TriangleBackups/iocage/images                                      188K   977G      188K  /mnt/TriangleBackups/iocage/images
TriangleBackups/iocage/jails                                       188K   977G      188K  /mnt/TriangleBackups/iocage/jails
TriangleBackups/iocage/log                                         188K   977G      188K  /mnt/TriangleBackups/iocage/log
TriangleBackups/iocage/releases                                    188K   977G      188K  /mnt/TriangleBackups/iocage/releases
TriangleBackups/iocage/templates                                   188K   977G      188K  /mnt/TriangleBackups/iocage/templates
freenas-boot                                                      8.67G  5.74G      176K  none
freenas-boot/ROOT                                                 8.64G  5.74G      136K  none
freenas-boot/ROOT/11.1-U7                                         17.2M  5.74G     1.01G  /
freenas-boot/ROOT/11.2-U6                                         15.7M  5.74G     1.03G  /
freenas-boot/ROOT/11.2-U8                                         11.6M  5.74G     1.03G  /
freenas-boot/ROOT/11.3-U5                                          352K  5.74G     1.34G  /
freenas-boot/ROOT/13.0-U3.1                                       8.57G  5.74G     1.59G  /
freenas-boot/ROOT/FreeNAS-12.0-U7                                  288K  5.74G     1.50G  /
freenas-boot/ROOT/Initial-Install                                    8K  5.74G     1.09G  legacy
freenas-boot/ROOT/Wizard-2018-12-27_08-06-02                         8K  5.74G     1.09G  legacy
freenas-boot/ROOT/default                                         17.9M  5.74G     1.11G  legacy
freenas-boot/grub                                                 7.94M  5.74G     7.94M  legacy

 

[tkimnguyen]

Code:

# cd /mnt/TriangleBackups/
# ls -l
total 18
drwxr-xr-x  2 www   www     2 Nov  4  2019 .freenas
drwxr-xr-x  9 root  wheel  11 Jan 10  2022 iocage
# df -h .
Filesystem         Size    Used   Avail Capacity  Mounted on
TriangleBackups    977G    188K    977G     0%    /mnt/TriangleBackups

 

[tkimnguyen]

Somewhat of an aside, the dashboard panel for the pool shows "Used space: 97%" with a red warning triangle next to it. What is that number? It does not seem to be documented and it doesn't match any figures I've been seeing.