[fedora-virt] QCOW2 vs QROW2 Disks

[Cole Robinson]

On 10/27/2012 04:37 PM, Jorge Fábregas wrote:
> Hi there,
> 
> I'm just curious:  Where does the "Copy on Write" (from QCOW) comes
> from?  Everything I've been reading regarding how snapshots work with
> QEMU points to a "redirect on write" approach.  Or is the COW part
> related to some other internal mechanism (not related to snapshots)?
> 

Probably a question for qemu-devel, but I think the qcow name was derived from
the cow format from user mode linux. The cow format's primary feature was
essentially qcow's backing_file file feature, so the name is likely derived
from that, and not necessarily qcow2's snapshotting abilities.

- Cole