Reclaiming free space

[heimos]

Hi,

I am running a RAIDZ setup with about 10TB of storage. My FreeNAS is setup to take snapshots every 30 minutes for two weeks. I have deleted a few hundred gigs of data from my SMB share but it does not properly reflect on the share. I deleted the snapshots that were taken up the space (sorted by used column) however that didn't help. What am I doing wrong? I am expecting to see a lot more free space.

zpool list:
NAME SIZE ALLOC FREE EXPANDSZ FRAG CAP DEDUP HEALTH ALTROOT
freenas-boot 59.5G 649M 58.9G - - 1% 1.00x ONLINE -
vol1 14.5T 14.0T 499G - 54% 96% 1.00x ONLINE /mnt

 

[SweetAndLow]

Is your pool 96% full? Does it actually delete the files when you do that? You should check out the ref field in snapshots to do what space they use .

Sent from my Nexus 5X using Tapatalk

 

[heimos]

It doesn't do that. About 2TB of files were deleted, but I am only seeing 20+ GB free. I started deleting snapshots but that does not help? Do I need to delete all of the snapshots that referenced deleted files? I have about two weeks worth of snapshots. Here is an example of ref field:

P.S. in my original post I said it was replicating every 30 minutes. it was actually set to every 5 minutes.

Space barely increased after deleting snapshots:

 

[heimos]

Is your pool 96% full? Does it actually delete the files when you do that? You should check out the ref field in snapshots to do what space they use .

Sent from my Nexus 5X using Tapatalk

Do those snapshots need to be deleted because they are holding the space from deleted files ? I posted a screenshot of my snapshots with the reference field.

 

[SweetAndLow]

Yes delete the snapshots if you can delete stuff.

Sent from my Nexus 5X using Tapatalk

 

[heimos]

How soon after deleting a snapshot should I see space increase ? I have deleted several large ones that I thought, but it only freed up a few gigs of space.

 

[heimos]

Yes delete the snapshots if you can delete stuff.

Sent from my Nexus 5X using Tapatalk

Yes delete the snapshots if you can delete stuff.

Sent from my Nexus 5X using Tapatalk

How soon after deleting a snapshot should I see space increase ? I have deleted several large ones that I thought, but it only freed up a few gigs of space.

 

[SweetAndLow]

The space instantly frees up. You should probably just delete all your snapshots if you don't need them. Or find the ones that reference the most data.

Sent from my Nexus 5X using Tapatalk

 

[heimos]

Is there a fast way of doing it ? I have about 1600 snapshots to go through :( plus I want to keep some of them at least one for each day for the past two weeks. Do they have a concept of chain, meaning you need a precious snapshot to recover a file or are they independed of each other.

I think I over killed it with snapshots every 5 minutes for two weeks. Maybe daily snapshots would be better.

 

[heimos]

The space instantly frees up. You should probably just delete all your snapshots if you don't need them. Or find the ones that reference the most data.

Sent from my Nexus 5X using Tapatalk

Is there a fast way of doing it ? I have about 1600 snapshots to go through :( plus I want to keep some of them at least one for each day for the past two weeks. Do they have a concept of chain, meaning you need a precious snapshot to recover a file or are they independed of each other.

I think I over killed it with snapshots every 5 minutes for two weeks. Maybe daily snapshots would be better.

 

[Jailer]

You won't gain the free space until all the snapshots that reference the data you deleted are removed.

 

[heimos]

You won't gain the free space until all the snapshots that reference the data you deleted are removed.

Ahhhgg that painful. So Let's says I had 14 snapshots for the same data vs. 1600 snapshots that I have now, would the space allocated for snapshots be different or the same ?

 

[Jailer]

would the space allocated for snapshots be different or the same ?

Depends on the data referenced at the time of the snapshot. But regardless of how many you have you won't see the free space until they are all deleted.

 

[snaptec]

if you delete a 150gb file that was created 15 days ago and this file is referecend in just one snapshot, you have to delete every single snapshot made in the last 15 days until the 150gb are free again.
It doesn't matter if it is in 1 or 1500 snapshots.

 

[heimos]

if you delete a 150gb file that was created 15 days ago and this file is referecend in just one snapshot, you have to delete every single snapshot made in the last 15 days until the 150gb are free again.
It doesn't matter if it is in 1 or 1500 snapshots.

But if the time passes and the deleted file is no longer on the share will the space automatically free up? Let's say snapshots are taken for 14 days and I delete the file 13 days ago. On day 15 the snapshot will not have that file referenced so will the space free up ?

 

[snaptec]

Yes.
If you created it 15 or more days ago. And delete it 10 days ago.
Every snapshot from day 10-15 must be deleted.
Then the space will automatically be free


Gesendet von iPhone mit Tapatalk

 

[fracai]

I have a script that I use to delete snapshots in bulk: https://github.com/fracai/zfs-rollup/blob/master/snap-strip.py

I recommend using it with the '--dryrun' argument to be sure it's doing what you want first.

 

[Jailer]

I think I over killed it with snapshots every 5 minutes for two weeks. Maybe daily snapshots would be better.

Or set up multiple snapshot tasks. Every 5 minutes that last for an hour. Hourly that last for a day. Daily that last for a week. Weekly that last for a month, etc. You don't have to do it all with one snapshot task.

 

[heimos]

Or set up multiple snapshot tasks. Every 5 minutes that last for an hour. Hourly that last for a day. Daily that last for a week. Weekly that last for a month, etc. You don't have to do it all with one snapshot task.

Will that save space ?

 

[snaptec]

only when you create a file in the morning, delete it 3 hours later and have the snapshot valid for just one day f.e.