On Thu, 24 Feb 2011 11:43:33 -0600 C Anthony Risinger <anthony@xxxxxxxx> wrote: > On Thu, Feb 24, 2011 at 11:23 AM, Jelle van der Waa <jelle@xxxxxxxx> > wrote: > > On Thu, 2011-02-24 at 11:07 -0600, C Anthony Risinger wrote: > >> hmm, soo qemu doesn't actually use the VT extensions? wtf is the > >> point then? > > QEMU is an emulator -> so for ARM for example > >> this is what i don't understand; if qemu supports KVM via > >> the `-enable-kvm` switch why does it suck so much -- it seems just > >> as slow to me as no KVM support at all. > > > > Here it's not, are you using qemu-kvm or some selfcompiled version? > > qemu-kvm is always fast. qemu is never fast -- libvirt uses > `-enable-kvm` when i tell it to, ie. for either package. i've tried > recompiling the regular `qemu` package with explicit KVM support, and > the speed is still absolutely abysmal. > > >> I have a server that runs > >> several KVM/libvirt instances (windows being one of them purely for > >> ... i dont even know) so i'm pretty familiar with it all, but i'm > >> just trying to get solid info why there is such a huge performance > >> gap when the both "use KVM". i thought KVM itself did all the VT > >> handling. > > > > Another tip for kvm usage is installing your OS on virtio [1] > > already do :-) i use all the virtio drivers -- when i say perf is bad > i mean it's like KVM isnt even working. i haven't `lsof` yet to make > sure qemu (not qemu-kvm!!) is actually opening the /dev/kvm device. > > i read thru the packages of both. i tried symlinking > `/usr/bin/qemu-kvm -> qemu-system-x86_64` (this is what qemu-kvm > package does) ... no difference. > > so my real question is, is anyone using the upstream package `qemu`, > with KVM, and getting proper results? are good results expected? > what am i missing here. > > C Anthony This is quite strange, I use qemu-system-x86_64 --enable-kvm regulary, and I get near native speed in the vm. [oh@Alice][~]% pacman -Q qemu qemu 0.14.0-1
