How do you backup qemu kvm OS host?

Question

Backup

Hey!
In general, there is an ubuntu server and qemu kvm is spinning there. Guest OS win8.1 It is
necessary to do backup with the different periods. For example, a rollback for 1 week and the ability to roll back on one of the days. Or maybe there is a way to view savepoints and roll back to them. In general, tell me the optimally convenient and reliable way to back up in such a situation for a short period (for example, 1 week).
Now I tried qemu snapshot, but I don’t know the intricacies of the kitchen and how to optimize the process too.
I heard about KLM
ps, did it become possible to make casts (reserves) without stopping?