SOLVED VM Performance with ZFS Deduplication

[adityaharsh]

I've two spare WD Red SN700 250GB and an existing mirror pool with 1TB Sabrent SSD for VMs.

I was thinking to add these 250GB drives as dedup drives, before creating a second VM, till now I've planned only to run Windows VMs on the 1TB disks and after watching this video I'm fully convinced. Still I want to know about the community's take on this. Thanks in advance for any valuable suggestions.

ZFS Deduplication in TrueNAS

Thanks to Manscaped for sponsoring today's video. Head over to https://Manscaped.com/CraftComputing to get 20% off your Performance Package 4.0 + Free Intern...

youtu.be

 

[Etorix]

ZFS has many advanced features which may be useful in some fringe cases, but are best ignored by the vast majority of users. Deduplication is one of them.

Deduplication is just not worth the resource costs for just TWO copies, and there's no need to speed up access to metadata with a mirror of NVMe drives.

 

[HoneyBadger]

I'm going to have to write a much longer and more technical reply to this, but the short version is that video sets up an extremely unrealistic and easy-win scenario for deduplication (just copying the same files to the share twice) so don't expect the same results.

 

[adityaharsh]

ZFS has many advanced features which may be useful in some fringe cases, but are best ignored by the vast majority of users. Deduplication is one of them.

Deduplication is just not worth the resource costs for just TWO copies, and there's no need to speed up access to metadata with a mirror of NVMe drives.

Actually that 1tb drive will eventually have 5 copies of windows, and this will be used in office environment, so the installation will be almost similar, that's why I considered this.

 

[xness]

Deduplication requires SSDs that can sustain simultaneous read-write operations. Especially when dealing with VM data instead of sequential data, I'm pretty sure the demand on the dedup vdev is even higher.

If you're serious about deduplication, I'd advice reading this: https://www.truenas.com/community/r...f-handling-fast-consistent-deduplication.148/

Though just to store 5 versions of Windows – aka just 250GB – you're better off just buying another SSD instead.

It's also said that VMs generally require the zpool to have around ~50% space left to work properly: https://www.truenas.com/community/r...and-why-we-use-mirrors-for-block-storage.112/

 

[adityaharsh]

Though just to store 5 versions of Windows – aka just 250GB – you're better off just buying another SSD instead.

It's also said that VMs generally require the zpool to have around ~50% space left to work properly

ya I have planned on using just 100gb for each VM because honestly that’s enough for my use case

Can something like this be achieved with TrueNAS Scale?

Can something like this be achieved with TrueNAS Scale? Basic Idea: 1) One Mirror Pool with 3 ZVols, each containing a Windows 11 VM ( I can create 3 different Pools if need be ) 2) Pass through 3 Nvidia A4000 to these three VMs respectively as the GPU 3) Output the VM i.e., Windows on an...

www.truenas.com

so I don’t think more than 1tb will be required for the time being