[libvirt] understanding managedsave

Hi, I'm trying to understand how the managedsave and restoration features work at the libvirt/qemu level. I'd like to write a little python script to reproduce the feature to learn how it works. So, I start a kvm guest by hand with qemu-kvm [...] -qmp tcp:localhost:4444,server and connect to the QMP with telnet or the qemu qmp-shell for my tests.

From what I've read, libvirt internally does a migration to a file: qemuDomainSaveMemory() -> qemuMonitorToFile() -> qemuMonitorMigrateToFd().

Why do a migration instead of QMP stop/memsave? What whould be the whole QMP/Monitor sequence of commands to handle the process? -- Nicolas Sebrecht