I wanted to start a topic for users that are doing the Hybrid ZFS setup with Native Unraid Array and ZFS formatted drives. 

 

Feel free to let me know how your performance has been after moving to ZFS.   

I am also looking for suggestions on how to optimize and improve the overall experience with Hybrid ZFS arrays in Unraid.

 

 

My only real tweak was to add to the boot drive config folder was modprobe.d zfs.conf to increase the the Archive Ram for ZFS. 

 

options zfs zfs_arc_max=64000000000

 

I played with Synoid and user scripts to take zfs snapshots of my appdata share for my dockers to do an alternative backup but have since stopped doing that cause I saw some weird issues with drives filing up during the process.

 

I am running zfs master but have refresh turned off.  I have not really grasped how to hand zfs snapshots and what the are legacy datasets in my zfs formated drives.  Would love to know what legacy mount points even exists.

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the legacy might be that your zpool was formatted with an earlier version of ZFS. Maybe an earlier Unraid version (I had ZFS on 6.12 already) or imported from TrueNAS or an y other ZFS supporting system?

9 hours ago, TCMapes said:

I am also looking for suggestions on how to optimize and improve the overall experience with Hybrid ZFS arrays in Unraid.

Optimize? easy: do not install it!

Overall experience: the worst idea you could ever have!

 

ZFS and UNRAID array cannot go together, they constantly fight each other and finally lock up the machine!

The more drives you have, the worse it will get.

 

This is, because ZFS has internal optimizing features that kick in now and then. And if they "cleanup" their ZFS partition, poor UNRAID parity drive(s) have to follow each write command.

If many ZFS pools run at the same time, drive 1 will send parity to track 32, drive 1 sends it to track 2345 and so on. The more you have, the more stepping will be needed.

This sums up to eating up all the io bandwith, blocking the whole machine.

 

Conclusion: ZFS in UNRAID array is a real NO GO!

 

(RAIDZ Arrays within an UNRAID Array are even more stupid, just a waste of diskspace because both do the same)

I think there is a misundertsanding on the premises of this. There is no "hybrid" anything. A pool in Unraid can only be an unraid pool for the main, and either ZFS or any of the BTRFS supported raid modes (raid 1, raid 0 for instance) on the other pools.

 

Having an individual disk formatted as ZFS brings nothing there. It will not be a ZFS pool and none of the features of ZFS will be available. They are not "mini ZFS pools".

If you want to use ZFS features, simply create an extra pool, outside of the main Unraid array (or no Unraid array, as it is now possible with 7.0 and later)

That is not my understanding of how Unraid Array behaves with ZFS.  You do get some benefits from the provide article, "https://unraid.net/blog/zfs-guide"



I am not running ZFS in separate pools just the drives are formatted as ZFS with no ZFS Pools.  I am just not sure if I need the Archive RAM feature of ZFS in the Unraid Array setup of ZFS.  I am actually hoping the newer version of Unraid will allow more of the native ZFS pool features.  Thought was doing this way would future proof me for where Unraid will ultimately go with Opting all features of ZFS in the native Unraid algo.

 

44 minutes ago, TCMapes said:

That is not my understanding of how Unraid Array behaves with ZFS.  You do get some benefits from the provide article

Yeah, that was the plan they have dreamed off... but then reality stroke...

The article should be deleted fast, its a pure wish (the "hybrid" part of it) and totally outdated.

 

If you like to try it out: you have been warned.

 

If you move back someday: welcome to the club! (the club fastly grew big after release of the feature!)

 

Edited March 14, 20251 yr by MAM59

51 minutes ago, MAM59 said:

Yeah, that was the plan they have dreamed off... but then reality stroke...

The article should be deleted fast, its a pure wish (the "hybrid" part of it) and totally outdated.

 

If you like to try it out: you have been warned.

 

If you move back someday: welcome to the club! (the club fastly grew big after release of the feature!)

 

So you are suggesting I go back to xfs for the array and not bother with ZFS?

6 minutes ago, TCMapes said:

So you are suggesting I go back to xfs for the array and not bother with ZFS?

This was the usual reaction of the club members that tried it out. If you search the forum, you will find dozens of sad people that tried "hybrid" and finally gave up.

 

XFS in the UNRAID array, ZFS only in seperate pools.

 

Edited March 14, 20251 yr by MAM59

Sounds good then I will abandon and start moving data with unbalanced so i can reformat my drives as xfs and my cache pools as btrfs

1 hour ago, TCMapes said:

and my cache pools as btrfs

Here zfs maybe the better option. "They" say btrfs is a bit of unstable, but I do not have bad experiences with it. But btrfs may disappear from Unraid sooner or later, so I would not put a new disk on in anymore.

Anyway zfs as a cache pool is ok.

 

 

Edited March 14, 20251 yr by MAM59

ZFS in the array is certainly viable. Having 1 or 2 ZFS disks allows for replication from cache(real-time backup of docker data without stopping containers) for example, plus the snapshotting, compression and scrubbing. 

Edited March 14, 20251 yr by foo_fighter

13 hours ago, MAM59 said:

But btrfs may disappear from Unraid sooner

That will never happen, unless btrfs is deprecated by Linux 

 

As for zfs on the array, it's a perfectly valid option, just be aware that as of now, there's a write performance issue with zfs on the array only, and also only if the source is faster, but it will hopefully be fixed soon.