From: Florian M?ller <max06.net@xxxxxxxxxxx> Sent: Monday, June 13, 2022 1:53 AM > > > >> > > > > > > >> > > > > Issues showed up when I set up a Kali Linux Guest. I missed > > >> > > > > the memory configuration before booting up the instance, so > > >> > > > > it started with 1GB of memory, and ballooning active between > > >> > > > > 512MB and several TB of memory. Hyper-V started to allocate > > >> > > > > more and more memory to this guest since the reported memory > > >> > > > > requirements also increased. The guest kernel didn't see any > > >> > > > > of that allocated memory, as far as I can tell. > > Please do not forget about this: (emoji-pointing-up) > Hmmm. Right off the bat, I don't know how to fix this. Hyper-V tells the guest "Here is more memory". The hv_balloon driver adds the memory (but doesn't mark it "online"), and sends a positive ACK to Hyper-V. >From Hyper-V's standpoint, it has successfully given the memory to the guest. But if the guest hasn't onlined the memory and isn't using it, the guest continues to report high memory pressure. Hyper-V assigns yet more memory to the guest, still to no effect. Having the hv_balloon driver delay the ACK until the memory comes online is fraught with problems, and of course Hyper-V has no visibility into whether the guest has onlined the memory. This may be one where the guest configuration really must be correct. But I'm open to other suggestions for a possible solution. Michael
