[pve-devel] [PATCH SERIES v2 pve-storage/qemu-server] add external qcow2 snapshot support

[DERUMIER, Alexandre]

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De: Esi Y via pve-devel <pve-devel at lists.proxmox.com>
Répondre à: Proxmox VE development discussion <pve-
devel at lists.proxmox.com>
À: Proxmox VE development discussion <pve-devel at lists.proxmox.com>
Cc: Esi Y <esiy0676+proxmox at gmail.com>
Objet: Re: [pve-devel] [PATCH SERIES v2 pve-storage/qemu-server] add
external qcow2 snapshot support
Date: 22/10/2024 11:51:31

> wasting developers time that then, among other things, delays actual

>>I hoped this would bump it up for Alexandre to get a response.
As far I remember, when we have implement snapshot for qcow2 (I think
in 2010~2011, I'm becoming old ^_^ ) , only internal snapshot was
possible, 
because they were no block-commit job. (to merge data in parent on
snapshot deletion).

Only block-stream job was available at this time (merge snapshot to
child snapshot)

I think that redhat have mostly worked on external snapshots these last
10years (mostly because they used them for backup, but also replication
where it's not possible with internal snasphot).

And the missing block job to merge data for internal snapshot is also
why the io need to be frozen during the merge.


So, that's why I never haved use qcow2 in production (mostly ceph,
or though custom netapp api for customer using nfs with raw files).

That mean that we don't have a clean snapshot solution currently for
shared san/nas without api.

I'm trying to fix/improve both nas (nfs) && san (iscsi,lvm) snapshots
implementation.

Mainly because I have a lot of onprem customers coming from vmware with
small san (iscsi/fiberchannel) needing snapshot feature.