Re: [Qemu-devel] [RFC] qemu snapshot enchancement

[Dietmar Maurer]

> >   * Like Case 2, the benefit isn't clear to me.  In a scenario where you
> >     use both QEMU and LVM snapshots there is now an extra management
> >     overhead of cleaning up 2 snapshots instead of just 1 when the user
> >     wants to delete a snapshot.  I think this will be a headache.
> >
>    My understanding is internal snapshots is obvious fast in both deleting and
> reading, and I have similar questions, Dietmar, could u tip more how you use
> this case while 2 snapshot layer exist?

To be honest, I don't really understand what you talk about here. There are 
simply 
different storage types and file formats. There are several storage types with
support for internal snapshots:

* traditional qcow2 files on normal file system
* newer file systems (zfs, btrfs)
* lvm (new dm-thin pools)
* RDB (ceph)
* sheepdog
* iSCSI and nexenta API
*...

And you simply want to allow an external library to create/remove the snapshot 
for you.