Removing RAM from VMs turns out to be actually quite tricky - hot-unplug very rarely works because the OS tends to have allocated stuff all over so you don't ha

Removing RAM from VMs turns out to be actually quite tricky - hot-unplug very rarely works because the OS tends to have allocated stuff all over so you don't have a nice large DIMM like quantity to unplug. Ballooning kind of works but it's more advisory, there's nothing to stop a guest gobbling that ram up again (and it has other issues). David Hildenbrand's Virtio-mem might help solve this; see: https://www.youtube.com/watch?v=H65FDUDPu9s https://www.youtube.com/watch?v=H65FDUDPu9s