TrueNas scale ElectricEel-24.10.2
1 Pool with 5x 4 TB disk using Raidz1 + 1 300 Gb disk for Dedup
2 Dataset inside the pool
Disk usage it show used a bit over 11TiB while i expect the real used space to be in between 5 and 6
zfs listoutput for the pool below
--------------------------------------------------
admin@plex-truenas[~]$ sudo zfs list|grep NAS
NAS 11.1T 3.27T 179K /mnt/NAS
NAS/.system 2.12G 3.27T 1.47G legacy
NAS/.system/configs-ae32c386e13840b2bf9c0083275e7941 27.0M 3.27T 27.0M legacy
NAS/.system/cores 153K 1024M 153K legacy
NAS/.system/netdata-ae32c386e13840b2bf9c0083275e7941 642M 3.27T 642M legacy
NAS/.system/nfs 236K 3.27T 236K legacy
NAS/.system/samba4 1.17M 3.27T 543K legacy
NAS/PLEX 5.52T 3.27T 5.52T /mnt/NAS/PLEX
NAS/ix-applications 9.16G 3.27T 850K /mnt/NAS/ix-applications
NAS/ix-applications/catalogs 62.7M 3.27T 62.7M /mnt/NAS/ix-applications/catalogs
NAS/ix-applications/default_volumes 153K 3.27T 153K /mnt/NAS/ix-applications/default_volumes
NAS/ix-applications/k3s 7.20G 3.27T 7.20G /mnt/NAS/ix-applications/k3s
NAS/ix-applications/k3s/kubelet 939K 3.27T 939K legacy
NAS/ix-applications/releases 1.89G 3.27T 932M /mnt/NAS/ix-applications/releases
NAS/ix-applications/releases/filebrowser 1.37M 3.27T 166K /mnt/NAS/ix-applications/releases/filebrowser
NAS/ix-applications/releases/filebrowser/charts 754K 3.27T 754K /mnt/NAS/ix-applications/releases/filebrowser/charts
NAS/ix-applications/releases/filebrowser/volumes 479K 3.27T 153K /mnt/NAS/ix-applications/releases/filebrowser/volumes
NAS/ix-applications/releases/filebrowser/volumes/ix_volumes 326K 3.27T 153K /mnt/NAS/ix-applications/releases/filebrowser/volumes/ix_volumes
NAS/ix-applications/releases/filebrowser/volumes/ix_volumes/config 173K 3.27T 173K /mnt/NAS/ix-applications/releases/filebrowser/volumes/ix_volumes/config
NAS/ix-applications/releases/netdata 3.03M 3.27T 166K /mnt/NAS/ix-applications/releases/netdata
NAS/ix-applications/releases/netdata/charts 1.78M 3.27T 1.78M /mnt/NAS/ix-applications/releases/netdata/charts
NAS/ix-applications/releases/netdata/volumes 1.09M 3.27T 153K /mnt/NAS/ix-applications/releases/netdata/volumes
NAS/ix-applications/releases/netdata/volumes/ix_volumes 959K 3.27T 166K /mnt/NAS/ix-applications/releases/netdata/volumes/ix_volumes
NAS/ix-applications/releases/netdata/volumes/ix_volumes/cache 524K 3.27T 1.64G /mnt/NAS/ix-applications/releases/netdata/volumes/ix_volumes/cache
NAS/ix-applications/releases/netdata/volumes/ix_volumes/config 115K 3.27T 198K /mnt/NAS/ix-applications/releases/netdata/volumes/ix_volumes/config
NAS/ix-applications/releases/netdata/volumes/ix_volumes/lib 153K 3.27T 217K /mnt/NAS/ix-applications/releases/netdata/volumes/ix_volumes/lib
NAS/ix-applications/releases/plex 34.5M 3.27T 166K /mnt/NAS/ix-applications/releases/plex
NAS/ix-applications/releases/plex/charts 1.27M 3.27T 1.27M /mnt/NAS/ix-applications/releases/plex/charts
NAS/ix-applications/releases/plex/volumes 33.0M 3.27T 153K /mnt/NAS/ix-applications/releases/plex/volumes
NAS/ix-applications/releases/plex/volumes/ix_volumes 32.9M 3.27T 166K /mnt/NAS/ix-applications/releases/plex/volumes/ix_volumes
NAS/ix-applications/releases/plex/volumes/ix_volumes/config 32.4M 3.27T 4.95G /mnt/NAS/ix-applications/releases/plex/volumes/ix_volumes/config
NAS/ix-applications/releases/plex/volumes/ix_volumes/data 102K 3.27T 153K /mnt/NAS/ix-applications/releases/plex/volumes/ix_volumes/data
NAS/ix-applications/releases/plex/volumes/ix_volumes/logs 89.5K 3.27T 153K /mnt/NAS/ix-applications/releases/plex/volumes/ix_volumes/logs
NAS/ix-applications/releases/plex/volumes/ix_volumes/transcode 141K 3.27T 555M /mnt/NAS/ix-applications/releases/plex/volumes/ix_volumes/transcode
NAS/ix-applications/releases/syncthing 969M 3.27T 166K /mnt/NAS/ix-applications/releases/syncthing
NAS/ix-applications/releases/syncthing/charts 959K 3.27T 959K /mnt/NAS/ix-applications/releases/syncthing/charts
NAS/ix-applications/releases/syncthing/volumes 968M 3.27T 153K /mnt/NAS/ix-applications/releases/syncthing/volumes
NAS/ix-applications/releases/syncthing/volumes/ix_volumes 967M 3.27T 153K /mnt/NAS/ix-applications/releases/syncthing/volumes/ix_volumes
NAS/ix-applications/releases/syncthing/volumes/ix_volumes/config 967M 3.27T 967M /mnt/NAS/ix-applications/releases/syncthing/volumes/ix_volumes/config
NAS/ix-apps 5.60T 3.27T 185K /mnt/.ix-apps
NAS/ix-apps/app_configs 6.78M 3.27T 6.78M /mnt/.ix-apps/app_configs
NAS/ix-apps/app_mounts 5.60T 3.27T 192K /mnt/.ix-apps/app_mounts
NAS/ix-apps/app_mounts/filebrowser 422K 3.27T 153K /mnt/.ix-apps/app_mounts/filebrowser
NAS/ix-apps/app_mounts/filebrowser/config 268K 3.27T 173K /mnt/.ix-apps/app_mounts/filebrowser/config
NAS/ix-apps/app_mounts/netdata 7.95G 3.27T 179K /mnt/.ix-apps/app_mounts/netdata
NAS/ix-apps/app_mounts/netdata/cache 7.95G 3.27T 1.73G /mnt/.ix-apps/app_mounts/netdata/cache
NAS/ix-apps/app_mounts/netdata/config 1.09M 3.27T 198K /mnt/.ix-apps/app_mounts/netdata/config
NAS/ix-apps/app_mounts/netdata/lib 1.66M 3.27T 281K /mnt/.ix-apps/app_mounts/netdata/lib
NAS/ix-apps/app_mounts/plex 5.59T 3.27T 179K /mnt/.ix-apps/app_mounts/plex
NAS/ix-apps/app_mounts/plex/config 15.3G 3.27T 5.69G /mnt/.ix-apps/app_mounts/plex/config
NAS/ix-apps/app_mounts/plex/data 5.57T 3.27T 153K /mnt/.ix-apps/app_mounts/plex/data
NAS/ix-apps/app_mounts/plex/logs 20.0M 3.27T 8.34M /mnt/.ix-apps/app_mounts/plex/logs
NAS/ix-apps/app_mounts/plex/transcode 649M 3.27T 555M /mnt/.ix-apps/app_mounts/plex/transcode
NAS/ix-apps/app_mounts/syncthing 1.92G 3.27T 153K /mnt/.ix-apps/app_mounts/syncthing
NAS/ix-apps/app_mounts/syncthing/config 1.92G 3.27T 973M /mnt/.ix-apps/app_mounts/syncthing/config
NAS/ix-apps/docker 1.98G 3.27T 1.98G /mnt/.ix-apps/docker
NAS/ix-apps/truenas_catalog 260M 3.27T 260M /mnt/.ix-apps/truenas_catalog
------------------------------------------------------------------------------
For some reason this appear to show 5.57 TB usage
/mnt/.ix-apps/app_mounts/plex/data
but then if i look inside is empty
----------------------------------------------------------
admin@plex-truenas[~]$ ls -la /mnt/.ix-apps/app_mounts/plex/data
total 1
drwxr-xr-x 2 apps apps 2 Mar 22 19:14 .
drwxr-xr-x 6 root root 6 Feb 4 11:43 ..
admin@plex-truenas[~]$ du /mnt/.ix-apps/app_mounts/plex/data
1 /mnt/.ix-apps/app_mounts/plex/data
why is that? What am I missing?
Please post your data using Preformatted Text (</>) or Ctrl+e going forward. It just makes it easier to read.
Do you have snapshots? Snapshots can be keeping the space used for filesystem changes. You also mention Dedup?
Arwen
March 25, 2025, 8:30am
3
For DeDup information, please supply the output of this command in CODE tags, (aka Preformatted Text):
zpool list -v NAS
admin@plex-truenas[~]$ sudo zpool list -v NAS
NAME SIZE ALLOC FREE CKPOINT EXPANDSZ FRAG CAP DEDUP HEALTH ALTROOT
NAS 18.5T 13.9T 4.54T - - 1% 75% 1.00x ONLINE /mnt
raidz1-0 18.2T 13.9T 4.25T - - 1% 76.6% - ONLINE
a240e7fb-47fd-4f03-8714-4117c19b45a9 3.64T - - - - - - - ONLINE
c51022cb-c068-415f-9336-5756271ce8a5 3.64T - - - - - - - ONLINE
6e7ef721-1d20-4778-97f3-dcc1da884030 3.64T - - - - - - - ONLINE
dd44c3f3-fa2a-4be3-8d88-6ba1eb2cd7f4 3.64T - - - - - - - ONLINE
77a1e80d-eec3-48c1-a66a-956cf83effef 3.64T - - - - - - - ONLINE
dedup - - - - - - - - -
643ad991-1a5c-496a-bed4-13fd35c0f2d6 298G 0 298G - - 0% 0.00% - ONLINE
``
no snapshot
etorix
March 25, 2025, 9:48am
8
If anything happens to the single dedup vdev, you lose the whole pool.
I’m aware. But that was not the question in this post
Arwen
March 25, 2025, 12:13pm
10
Looks like you don’t even use DeDup. It has to be enabled, preferably with a higher level checksum than the default.
Snapshots are generally the cause of higher than expected space usage. Please supply the output of the following command in CODE tags;
sudo zfs list -t all -r NAS
I’m relatively new to TrueNAs and still experimenting on the dedup part I still understanding how it works, so if you can point me to some article explaining how to actually enable it i’ll appreciate it
As far as I can see there are no snapshot (I had but I removed)
for some context the folder data that is reporting the 5,5 TB had data in it and I deleted manually from CLI but the space usage did not change
here is the output requested
admin@plex-truenas[~]$ sudo zfs list -t all -r NAS
NAME USED AVAIL REFER MOUNTPOINT
NAS 11.1T 3.27T 179K /mnt/NAS
NAS/.system 2.09G 3.27T 1.47G legacy
NAS/.system/configs-ae32c386e13840b2bf9c0083275e7941 27.1M 3.27T 27.1M legacy
NAS/.system/cores 153K 1024M 153K legacy
NAS/.system/netdata-ae32c386e13840b2bf9c0083275e7941 615M 3.27T 615M legacy
NAS/.system/nfs 236K 3.27T 236K legacy
NAS/.system/samba4 1.17M 3.27T 543K legacy
NAS/.system/samba4@update--2025-02-03-10-11--SCALE-24.04.2 262K - 435K -
NAS/.system/samba4@update--2025-02-04-08-40--SCALE-24.04.2.5 364K - 537K -
NAS/PLEX 5.52T 3.27T 5.52T /mnt/NAS/PLEX
NAS/ix-applications 9.16G 3.27T 850K /mnt/NAS/ix-applications
NAS/ix-applications/catalogs 62.7M 3.27T 62.7M /mnt/NAS/ix-applications/catalogs
NAS/ix-applications/default_volumes 153K 3.27T 153K /mnt/NAS/ix-applications/default_volumes
NAS/ix-applications/k3s 7.20G 3.27T 7.20G /mnt/NAS/ix-applications/k3s
NAS/ix-applications/k3s/kubelet 939K 3.27T 939K legacy
NAS/ix-applications/releases 1.89G 3.27T 932M /mnt/NAS/ix-applications/releases
NAS/ix-applications/releases/filebrowser 1.37M 3.27T 166K /mnt/NAS/ix-applications/releases/filebrowser
NAS/ix-applications/releases/filebrowser/charts 754K 3.27T 754K /mnt/NAS/ix-applications/releases/filebrowser/charts
NAS/ix-applications/releases/filebrowser/volumes 479K 3.27T 153K /mnt/NAS/ix-applications/releases/filebrowser/volumes
NAS/ix-applications/releases/filebrowser/volumes/ix_volumes 326K 3.27T 153K /mnt/NAS/ix-applications/releases/filebrowser/volumes/ix_volumes
NAS/ix-applications/releases/filebrowser/volumes/ix_volumes/config 173K 3.27T 173K /mnt/NAS/ix-applications/releases/filebrowser/volumes/ix_volumes/config
NAS/ix-applications/releases/netdata 3.03M 3.27T 166K /mnt/NAS/ix-applications/releases/netdata
NAS/ix-applications/releases/netdata/charts 1.78M 3.27T 1.78M /mnt/NAS/ix-applications/releases/netdata/charts
NAS/ix-applications/releases/netdata/volumes 1.09M 3.27T 153K /mnt/NAS/ix-applications/releases/netdata/volumes
NAS/ix-applications/releases/netdata/volumes/ix_volumes 959K 3.27T 166K /mnt/NAS/ix-applications/releases/netdata/volumes/ix_volumes
NAS/ix-applications/releases/netdata/volumes/ix_volumes/cache 524K 3.27T 1.64G /mnt/NAS/ix-applications/releases/netdata/volumes/ix_volumes/cache
NAS/ix-applications/releases/netdata/volumes/ix_volumes/config 115K 3.27T 198K /mnt/NAS/ix-applications/releases/netdata/volumes/ix_volumes/config
NAS/ix-applications/releases/netdata/volumes/ix_volumes/lib 153K 3.27T 217K /mnt/NAS/ix-applications/releases/netdata/volumes/ix_volumes/lib
NAS/ix-applications/releases/plex 34.5M 3.27T 166K /mnt/NAS/ix-applications/releases/plex
NAS/ix-applications/releases/plex/charts 1.27M 3.27T 1.27M /mnt/NAS/ix-applications/releases/plex/charts
NAS/ix-applications/releases/plex/volumes 33.0M 3.27T 153K /mnt/NAS/ix-applications/releases/plex/volumes
NAS/ix-applications/releases/plex/volumes/ix_volumes 32.9M 3.27T 166K /mnt/NAS/ix-applications/releases/plex/volumes/ix_volumes
NAS/ix-applications/releases/plex/volumes/ix_volumes/config 32.4M 3.27T 4.95G /mnt/NAS/ix-applications/releases/plex/volumes/ix_volumes/config
NAS/ix-applications/releases/plex/volumes/ix_volumes/data 102K 3.27T 153K /mnt/NAS/ix-applications/releases/plex/volumes/ix_volumes/data
NAS/ix-applications/releases/plex/volumes/ix_volumes/logs 89.5K 3.27T 153K /mnt/NAS/ix-applications/releases/plex/volumes/ix_volumes/logs
NAS/ix-applications/releases/plex/volumes/ix_volumes/transcode 141K 3.27T 555M /mnt/NAS/ix-applications/releases/plex/volumes/ix_volumes/transcode
NAS/ix-applications/releases/syncthing 969M 3.27T 166K /mnt/NAS/ix-applications/releases/syncthing
NAS/ix-applications/releases/syncthing/charts 959K 3.27T 959K /mnt/NAS/ix-applications/releases/syncthing/charts
NAS/ix-applications/releases/syncthing/volumes 968M 3.27T 153K /mnt/NAS/ix-applications/releases/syncthing/volumes
NAS/ix-applications/releases/syncthing/volumes/ix_volumes 967M 3.27T 153K /mnt/NAS/ix-applications/releases/syncthing/volumes/ix_volumes
NAS/ix-applications/releases/syncthing/volumes/ix_volumes/config 967M 3.27T 967M /mnt/NAS/ix-applications/releases/syncthing/volumes/ix_volumes/config
NAS/ix-apps 5.60T 3.27T 185K /mnt/.ix-apps
NAS/ix-apps/app_configs 6.78M 3.27T 6.78M /mnt/.ix-apps/app_configs
NAS/ix-apps/app_mounts 5.60T 3.27T 192K /mnt/.ix-apps/app_mounts
NAS/ix-apps/app_mounts/filebrowser 422K 3.27T 153K /mnt/.ix-apps/app_mounts/filebrowser
NAS/ix-apps/app_mounts/filebrowser@1.2.8 0B - 153K -
NAS/ix-apps/app_mounts/filebrowser/config 268K 3.27T 173K /mnt/.ix-apps/app_mounts/filebrowser/config
NAS/ix-apps/app_mounts/filebrowser/config@1.2.8 95.9K - 173K -
NAS/ix-apps/app_mounts/netdata 8.08G 3.27T 179K /mnt/.ix-apps/app_mounts/netdata
NAS/ix-apps/app_mounts/netdata@1.2.13 0B - 179K -
NAS/ix-apps/app_mounts/netdata@1.2.14 0B - 179K -
NAS/ix-apps/app_mounts/netdata@1.2.18 0B - 179K -
NAS/ix-apps/app_mounts/netdata/cache 8.08G 3.27T 1.73G /mnt/.ix-apps/app_mounts/netdata/cache
NAS/ix-apps/app_mounts/netdata/cache@5 1.33G - 1.41G -
NAS/ix-apps/app_mounts/netdata/cache@6 852M - 1.42G -
NAS/ix-apps/app_mounts/netdata/cache@7 968M - 1.50G -
NAS/ix-apps/app_mounts/netdata/cache@ix-applications-backup-system-update--2025-02-03_10:11:11 131M - 1.63G -
NAS/ix-apps/app_mounts/netdata/cache@9 17.9M - 1.62G -
NAS/ix-apps/app_mounts/netdata/cache@ix-applications-backup-system-update--2025-02-04_08:40:52 14.2M - 1.64G -
NAS/ix-apps/app_mounts/netdata/cache@1.2.13 15.4M - 1.64G -
NAS/ix-apps/app_mounts/netdata/cache@1.2.14 830M - 1.72G -
NAS/ix-apps/app_mounts/netdata/cache@1.2.18 158M - 1.73G -
NAS/ix-apps/app_mounts/netdata/config 1.09M 3.27T 198K /mnt/.ix-apps/app_mounts/netdata/config
NAS/ix-apps/app_mounts/netdata/config@5 102K - 198K -
NAS/ix-apps/app_mounts/netdata/config@6 102K - 198K -
NAS/ix-apps/app_mounts/netdata/config@7 102K - 198K -
NAS/ix-apps/app_mounts/netdata/config@ix-applications-backup-system-update--2025-02-03_10:11:11 102K - 198K -
NAS/ix-apps/app_mounts/netdata/config@9 102K - 198K -
NAS/ix-apps/app_mounts/netdata/config@ix-applications-backup-system-update--2025-02-04_08:40:52 102K - 198K -
NAS/ix-apps/app_mounts/netdata/config@1.2.13 102K - 198K -
NAS/ix-apps/app_mounts/netdata/config@1.2.14 102K - 198K -
NAS/ix-apps/app_mounts/netdata/config@1.2.18 102K - 198K -
NAS/ix-apps/app_mounts/netdata/lib 1.66M 3.27T 281K /mnt/.ix-apps/app_mounts/netdata/lib
NAS/ix-apps/app_mounts/netdata/lib@5 141K - 192K -
NAS/ix-apps/app_mounts/netdata/lib@6 141K - 192K -
NAS/ix-apps/app_mounts/netdata/lib@7 141K - 192K -
NAS/ix-apps/app_mounts/netdata/lib@ix-applications-backup-system-update--2025-02-03_10:11:11 141K - 192K -
NAS/ix-apps/app_mounts/netdata/lib@9 153K - 204K -
NAS/ix-apps/app_mounts/netdata/lib@ix-applications-backup-system-update--2025-02-04_08:40:52 166K - 217K -
NAS/ix-apps/app_mounts/netdata/lib@1.2.13 166K - 217K -
NAS/ix-apps/app_mounts/netdata/lib@1.2.14 192K - 275K -
NAS/ix-apps/app_mounts/netdata/lib@1.2.18 179K - 262K -
NAS/ix-apps/app_mounts/plex 5.59T 3.27T 179K /mnt/.ix-apps/app_mounts/plex
NAS/ix-apps/app_mounts/plex@1.1.14 0B - 179K -
NAS/ix-apps/app_mounts/plex/config 15.6G 3.27T 5.69G /mnt/.ix-apps/app_mounts/plex/config
NAS/ix-apps/app_mounts/plex/config@11 2.23G - 4.18G -
NAS/ix-apps/app_mounts/plex/config@17 1.95G - 4.11G -
NAS/ix-apps/app_mounts/plex/config@20 1.79G - 4.93G -
NAS/ix-apps/app_mounts/plex/config@ix-applications-backup-system-update--2025-02-03_10:11:11 288M - 5.20G -
NAS/ix-apps/app_mounts/plex/config@ix-applications-backup-system-update--2025-02-04_08:40:52 22.2M - 4.95G -
NAS/ix-apps/app_mounts/plex/config@1.1.14 1.22G - 5.36G -
NAS/ix-apps/app_mounts/plex/data 5.57T 3.27T 153K /mnt/.ix-apps/app_mounts/plex/data
NAS/ix-apps/app_mounts/plex/data@11 729K - 5.07T -
NAS/ix-apps/app_mounts/plex/data@17 614K - 5.14T -
NAS/ix-apps/app_mounts/plex/data@20 1.07M - 5.25T -
NAS/ix-apps/app_mounts/plex/data@ix-applications-backup-system-update--2025-02-03_10:11:11 307K - 5.57T -
NAS/ix-apps/app_mounts/plex/data@ix-applications-backup-system-update--2025-02-04_08:40:52 12.8K - 5.57T -
NAS/ix-apps/app_mounts/plex/data@1.1.14 12.8K - 5.57T -
NAS/ix-apps/app_mounts/plex/logs 26.6M 3.27T 14.9M /mnt/.ix-apps/app_mounts/plex/logs
NAS/ix-apps/app_mounts/plex/logs@11 0B - 153K -
NAS/ix-apps/app_mounts/plex/logs@17 0B - 153K -
NAS/ix-apps/app_mounts/plex/logs@20 0B - 153K -
NAS/ix-apps/app_mounts/plex/logs@ix-applications-backup-system-update--2025-02-03_10:11:11 0B - 153K -
NAS/ix-apps/app_mounts/plex/logs@ix-applications-backup-system-update--2025-02-04_08:40:52 0B - 153K -
NAS/ix-apps/app_mounts/plex/logs@1.1.14 11.6M - 12.6M -
NAS/ix-apps/app_mounts/plex/transcode 649M 3.27T 555M /mnt/.ix-apps/app_mounts/plex/transcode
NAS/ix-apps/app_mounts/plex/transcode@11 166K - 555M -
NAS/ix-apps/app_mounts/plex/transcode@17 92.4M - 648M -
NAS/ix-apps/app_mounts/plex/transcode@20 179K - 555M -
NAS/ix-apps/app_mounts/plex/transcode@ix-applications-backup-system-update--2025-02-03_10:11:11 179K - 555M -
NAS/ix-apps/app_mounts/plex/transcode@ix-applications-backup-system-update--2025-02-04_08:40:52 179K - 555M -
NAS/ix-apps/app_mounts/plex/transcode@1.1.14 192K - 555M -
NAS/ix-apps/app_mounts/syncthing 1.92G 3.27T 153K /mnt/.ix-apps/app_mounts/syncthing
NAS/ix-apps/app_mounts/syncthing@1.1.11 0B - 153K -
NAS/ix-apps/app_mounts/syncthing/config 1.92G 3.27T 973M /mnt/.ix-apps/app_mounts/syncthing/config
NAS/ix-apps/app_mounts/syncthing/config@1.1.11 995M - 995M -
NAS/ix-apps/docker 1.98G 3.27T 1.98G /mnt/.ix-apps/docker
NAS/ix-apps/truenas_catalog 262M 3.27T 262M /mnt/.ix-apps/truenas_catalog
Arwen
March 26, 2025, 6:02pm
12
In general, if you have to ask about ZFS DeDup, you should not be using it. Their is an improved version coming out soon, Fast DeDup. But I won’t use it for at least a year after release. Let all the others be guinea pigs.
ZFS DeDup can lead to data loss if used improperly. We had had occasional people get their DeDupped Datasets so large they can’t import them after crash, reboot or update. That is because other services may take up memory that is eventually needed for the DeDup table on pool import.
However, the user can’t import the pool to fix the problem until the have more memory. Catch 22.
The Special Allocation Device you have allocated for DeDup does not over-come the need for memory. Just improves access to the DeDup table during import and during writes that are DeDupped. I vaguely recall the ability to use an L2ARC device as a spill location for DeDup memory. But, don’t ask me the details because that is all I have.
Here is what I wrote some years ago about De-Dup:
The TrueNAS forums occasionally have people who come across ZFS de-duplicate, and want to investigate its use. Or think it is a good idea, and want to implement it.
Here are some suggested configuration details:
Understand that you need CPU...
As for your space usage, seems like Plex doubled up your media. You have to be very careful fixing this, because I am assuming you don’t want to loose any of your media. Here is what I mean:
NAS/PLEX 5.52T 3.27T 5.52T /mnt/NAS/PLEX
...
NAS/ix-apps/app_mounts/plex/data 5.57T 3.27T 153K /mnt/.ix-apps/app_mounts/plex/data
I do love the title of the article so I’ll leave disable for now, and one day I’ll rebuild the pool I’ll reassigned the disk differently because from some research I did there is no way to unassign the dedup disk. As for space usage yes I reached the same conclusion but data inside the ix pool is empty I can’t understand what is taking space.
I might end un rebuilt the pool ( have some issue with the disks for the backup, once fixed and ensured backup is done I’ll probably rebuild. Any advice what would be best usage of that 300 gb disk? ( As you probably understood the pool is entirely dedicated for Plex)