Re: [Qemu-devel] RFC: moving fsfreeze support from the userland guest agent to the guest kernel

[Ronen Hod]

Well, we want to support Microsoft's VSS, and that requires a guest 
agent that communicates with all the "writers" (applications), waiting 
for them to flush their app data in order to generate a consistent 
app-level snapshot. The VSS platform does most of the work.
Still, at the bottom line, the agent's role is only to find the right 
moment in time. This moment can be relayed back to libvirt, and from 
there do it according to your suggestion, so that the guest agent does 
not do the freeze, and it is actually not a mandatory component.

Ronen.