(2012/11/14 18:44:44), Daniel P. Berrange wrote: > On Wed, Nov 14, 2012 at 03:10:48AM +0000, Ichikawa, Ken wrote: > > Now, qemu guest's default cpu model is qemu32/64 and it can be > > configured per domain. In some case, host-model mode is suitable for > > getting enough performance in the guest because of features from cpu > > spec. > > > > This patch adds a config option to qemu.conf to use 'host-model' > > mode as default and allow users to use host-model mode in domains on a host. > > This is useful because > > - Guest owners don't need to touch their domain's config. > > - An administrator can reduce an item in their checklist for VM > > performance and guarantee all guests should run in the best > performance. > > While I understand the benefits, I'm afraid I have to NACK this at > this time because using host-model doesn't really work when trying to > use nested-KVM. Until we have a solution for that, we neeed to stick > with a CPU model that works everywhere, since users like OpenStack do > actually use nested-KVM for testing work and already complained about > this when I made OpenStack set the host-model by default. Thank you for noticing the nested-KVM problem. However, to enable this patch's function, users need to edit qemu.conf. So, if users use nested-KVM, they just don't edit the conf file. Is there still any problem? Ken ICHIKAWA -- libvir-list mailing list libvir-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvir-list