[libvirt] [PATCH] rbd: Use rbd_create3 to create RBD format 2 images by default

[Wido den Hollander]

On 01/02/2014 08:42 PM, Doug Goldstein wrote:
> On Thu, Jan 2, 2014 at 10:01 AM, Wido den Hollander <wido at widodh.nl> wrote:
>>
>>
>> On 12/11/2013 03:47 PM, Wido den Hollander wrote:
>>>
>>> This new RBD format supports snapshotting and cloning. By having
>>> libvirt create images in format 2 end-users of the created images
>>> can benefit of the new RBD format.
>>>
>>> Older versions of libvirt can work with this new RBD format as long
>>> as librbd supports format 2, something that all recent versions of
>>> librbd do.
>>>
>>
>> Did somebody get a look at this patch yet? It's a fairly simple one, but
>> would be great for the Ceph project!
>>
>
> So I'm thinking we might want to do something similar with the compat
> attribute added for qcow2 for the versioning that way things are
> explicitly stated rather than implicitly switching versions on us.
>

Problem is that we are linking to a library here on compile time and not 
executing a binary to create the image.

The Ceph project is still very new, almost nobody is actually using the 
format 1 images anymore. I wouldn't recommend anybody creating format 1 
images now.

They still work just fine, but we don't want to encourage people to keep 
using them.

Wido