Loss of disk space / disk size reduced

Hello everyone,

I hope I’m posting in the right place because I admit I’m a little lost…

I’ll try to explain my issue:
yesterday, I deleted about 650GB of photos from my Windows 11 computer, and everything seemed fine.
However, this morning, I realized that this deletion has reduced the total space on my disks. I have two 4TB disks set up in a mirror configuration, so I should normally have 3.6TB of available space.
However, since this deletion, I now only have 2.2TB available… I’ve searched for a solution to my problem on various forums, and I found someone who had the same issue here: Loss of disk space / disk size reduced | TrueNAS Community but without any conclusive results.

So, I’m reaching out to you in the hope of finding a possible solution to my problem.

Thank you in advance! :blush:

What is the output of zpool list poolname? I assume you are using SMB?

Thank you for your reply,

Yes i use SMB

Data 3.62T 3.01T 626G   -        -     0%  83% 1.00x ONLINE /mnt

What about this output?

zfs list -o space -r poolname

I am wondering if you have some snapshots using up all the space

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This shows your pool has around 600GB of unused space; as @Tyler_Shield pointed out it’s possible that you are using space for snapshots and that’s why your math doesn’t add up.

In windows if file history is on then the files are still there but moved to a history file and multiple histories can be saved. If file history was on and you turned it off, then old file histories of files are still there but newer ones will not be written. If you have onedrive then this eats up local disk space in some cases. Some have reported file history eventually eats all the disk space and only option is a reformat.-Thanks windowz.

In my windows 11 laptop I think file history was on by default.

If you have the recycle bin enabled on Truenas share, then the files may be in the recycle bin taking up space.Snapshots is another place that may need looking at. You may have a series of snapshots in Truenas from from any Truenas snapshots done containing those files and their changes. Space used for them won’t change until they expire.

to be honest I’m new to using TrueNAS so I don’t really know where to look.

by entering the command you cited above I obtain this :

Data 510G 3.01T 0B 104K 0B 3.01T
Data/Stockage 510G 3.01T 1.28T 1.73T 0B 0B

I don’t have file history enabled in Windows and Recycle Bin isn’t enabled in TrueNAS…
This is why I don’t understand where the problem comes from and my last resort is formatting the disks but if I could avoid this happening… :sweat_smile:

oh my god I completely missed this… I ACTUALLY had a snapshot that was created after my big file sharing… It was 1.2T thank you and sorry for having made a post for such a stupid mistake.

A question is never stupid!

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I explain snapshots, configuring them, using them, and how to recover space when deleting them in some detail in this video

Might be worth checking out :slight_smile: