Comment 3 for bug 1185851

Zhi, cinder currently leverages the Glance v2 api to allow the user to do fast cloning of glance images when creating volumes. If the user wants to do a full copy and manage the cloning withing cinder they can switch to using the v1 api instead. The value of giving the option to clone from glance rather than force a copy is at least one of performance and capacity saving. The solution proposed here *should* be fairly simple thus allowing to keep supporting this flexible approach for the user.