In place resize of memory

[Tobias Rydberg]

Nova currently does not interface with libvirt and virtio to do memory ballooning. A blueprint for this has existed for 4 years, but was never implemented. Adding more memory to a guest is currently possible only by means of a flavor change, which always causes the guest to be stopped and restarted.

Nova developers might argue that it's somewhat un-cloudy for an application to rely on in-place scale-up of a guest's RAM, but that argument is rather moot considering this feature has already been implemented for Hyper-V.

Related links:

https://blueprints.launchpad.net/nova/+spec/libvirt-memory-ballooning (libvirt blueprint, not started)

https://blueprints.launchpad.net/nova/+spec/hyper-v-dynamic-memory (corresponding feature for Hyper-V, implemented in Havana)

[Matt Riedemann (mriedem)]

There is an instance live resize spec proposed:

https://review.openstack.org/#/c/141219/

Does that satisfy the requirement? It supports resizing up and down except not down for disk.