Re: [libvirt] [PATCH 0/8] logically memory hotplug via guest agent

On Tue, Jun 09, 2015 at 13:05:35 +0100, Daniel Berrange wrote: > On Tue, Jun 09, 2015 at 02:03:13PM +0200, Peter Krempa wrote: > > On Tue, Jun 09, 2015 at 12:46:27 +0100, Daniel Berrange wrote: > > > On Tue, Jun 09, 2015 at 01:22:49PM +0200, Peter Krempa wrote: > > > > On Tue, Jun 09, 2015 at 11:05:16 +0100, Daniel Berrange wrote: > > > > > On Tue, Jun 09, 2015 at 05:33:24PM +0800, Zhang Bo wrote: > > > > ... > > > > 2) The guest OS sometimes needs to enable the memory region after ACPI > > > > memory hotplug. The GA would be able to online such memory. For this > > > > option we don't need to go through a different API though since it can > > > > be compounded using a flag. > > > > > > So, are you saying that we should not be adding this to the > > > virDomainSetMemory API as done in this series, and we should > > > instead be able to request automatic enabling/disabling of the > > > regions when we do the original DIMM hotplug ? > > > > Well, that's the only place where using the memory region GA apis would > > make sense for libvirt. > > > > Whether we should do it is not that clear. Windows does online the > > regions automatically and I was told that some linux distros do it via > > udev rules. > > What do we do in the case of hotunplug currently ? Are we expectig the > guest admin to have manually offlined the regions before doing hotunplug > on the host ? You don't need to offline them prior to unplug. The guest OS handles that automatically when it receives the request.