It takes a lot to distract me from NFL playoff football, and this retweet by Didier Van Hoye (MVP) accomplished that:
Oooh! Ballooning is the process that allows the Dynamic Memory Virtual Service Client (DMVSC) to remove unused memory from a running virtual machine.
A bit more digging led to a site called Golem.de that is written in German. My German is very limited (mainly to asking for a beer and saying I have a hotel room served) so I ran the page through a translator. Here is it what it says about AArch64 in Linux Kernel 3.8 (code submissions recently ended):
Of Microsoft hyper+ V driver can deal in the future with Ballooning. That is to optimize the use of the main memory through under Linux virtualisierte Windows systems.
I kept Googling because one site is not enough to satisfy me on this. And then I found something in Google Groups. It appears to be a conversation between one person and a Dr. K.Y. Srinivasan from the Server division in Microsoft, dealing with Linux integration.
Note: Zoominfo is a robot, and a pretty dumb one at that. It thinks I work for Microsoft, which I do not and never have.
The balloon driver is mentioned, but there is a function to get committed memory in a VM. That’s important: how much memory is being used, versus how much is not. How much pressure is there, and how much memory does the VM need?
I am not saying that Dynamic Memory is coming to Hyper-V. That has not been announced. But the evidence sure adds up that DM functionality is being added to the Linux Integration Services. That will be great for Linux on Hyper-V, and that will be awesome for public clouds (hosting) and private clouds (large enterprise virtualisation).