On Mon, 18 Feb 2019 16:36:30 +0100 David Hildenbrand <david@xxxxxxxxxx> wrote: > >> Do we know the size of the device mappings upfront (So that we can setup > >> the max memory size)? > >> Something like > >> 4GB guest + 2 deviced with 1TB each. So we would set the max memory size > >> to 2.004TB > > > > For a non-hotplugged device, we should know. For hotplugged, this is > > more difficult; maybe we can fail it if a pre-alloced pool is exhausted? > > We can > a) make it configurable similar to maxmem (e.g. machine property) > b) guarantee a minimum size (e.g. X GB) we can glue to compat machines. > > Especially we should also provide a way to disable it completely, for > small guests. (can also be done via such a parameter) And make device realization resp. hotplug fail if we can't get a memory chunk for its regions? Makes sense. Dynamically changing the size would probably open a whole different can of worms; hopefully we can avoid going there. > > In addition, the "max out current address space size" can always be done > without issues.
