Meaning of <<INFO: backup is sparse:>> during VM backup

[ieronymous]

Hi

i d like to know what is the meaning of ......... INFO: backup is sparse: 54.26 GiB (49%) total zero data,
even though it seems to finish successfully .

.... and the rest of the message
INFO: transferred 109.00 GiB in 731 seconds (152.7 MiB/s)
INFO: archive file size: 39.43GB
INFO: adding notes to backup
INFO: Finished Backup of VM 103 (00:12:16)
INFO: Backup finished at 2022-05-20 21:48:01
INFO: Backup job finished successfully
TASK OK

 

[bbgeek17]

It means that your VM that takes 109GiB of space, contains 54.26GiB of zeros. Nothing unusual. Probably thin provisioning inside and outside of VM.

---

Blockbridge : Ultra low latency all-NVME shared storage for Proxmox - https://www.blockbridge.com/proxmox

 

[ieronymous]

It means that your VM that takes 109GiB of space, contains 54.26GiB of zeros. Nothing unusual. Probably thin provisioning inside and outside of VM.

---

Blockbridge : Ultra low latency all-NVME shared storage for Proxmox - https://www.blockbridge.com/proxmox

Probably each of the backups may had this message, but just noticed it . Since the meaning of sparse is something which is here and there it felt like the backup doesn t consistency or something

 

[ieronymous]

Probably thin provisioning inside and outside of VM

Outside is managed automatically depending if the underline storage has been created as such (thin provision). Inside the VM how you check it?
Can you set it as thin provision enable / disable inside the VM somehow?