Thin provisioning - Advantages and Disadvantages for use in ZFS ?

[bitblue.lab]

I was thinking is there any disadvantages using Thin provisioning in ZFS storage pools? ZFS has many features including compression so I was thinking if compression is turned on and Thin provisioning used can it help to save space and use more VM-s or data in Drives.

Any experience with that in production ?

 

[sigxcpu]

I use ZFS overprovisioning with or without compression for years. No issues, except you don't want to fill the VM disks.
I do that to use a big disk template for VMs. Some use the big disk size, some don't, so they all fit inside the bigger storage pool.

 

[bitblue.lab]

so if a disk of 200GB gets used only 130 GB and after using to 130GB it removes files and goes to 20GB ( does in storage pool this works I mean does it go again to 20GB or stays full as where it was before )

 

[sigxcpu]

It depends.

For zvols, using VIRTIO-SCSI as the disk driver will pass-through UNMAP requests from the guest and the underlying volume will honor them.

 

[bitblue.lab]

It depends.

For zvols, using VIRTIO-SCSI as the disk driver will pass-through UNMAP requests from the guest and the underlying volume will honor them.

So with VIRTIO-SCSI I will have no problem and no speed degradation ?

 

[sigxcpu]

Your original question was about recovering size of deleted files. Where does this fit "no problem" and "no speed degradation"?

 

[vkhera]

So with VIRTIO-SCSI I will have no problem and no speed degradation ?

You will have no problem. As for speed, you'll have to measure it. I do not perceive any speed degradation but I did not do formal benchmarking.