Re: What's wrong with internal VM snapshots?
On Mon, May 06, 2024 at 11:10:57 +0300, Marius Vollmer wrote:
Peter Krempa <pkrempa(a)redhat.com> writes:
> On Mon, May 06, 2024 at 10:03:23 +0300, Marius Vollmer wrote:
>
>> I see, thanks! So, would it be fair to say that internal snapshots
>> are deprecated by upstream libvirt itself (since 0.10), not just in
>> RHEL?
[ version 10, not 0.10. Sorry, no idea why I thought you are on
0.10... ]
> No that is not fair to say from upstream point of view. We do not plan
> to remove the functionality and will accept any form of improvements.
> Same applies for qemu.
Ok! Are external snapshots preferred over internal ones?
External snapshots are preferred in the terms that they got more
development recently. Internal snapshots are still lacking the refactor
to new QEMU APIs which would allow libvirt using them more effectively.
How should a
user decide which format to use when both are possible in a given
situation?
It really depends on what the user wants. Internal snapshots are more
self-contained, thus the user might prefer them if they want to move the
image around. External snapshots, on the other hand, allow more control
where the data is present and are possible even if the original image is
not yet qcow2 (or other supporting internal snapshots).
Libvirt will need to default to internal snapshots to preserve
historical compatibility.