<p><i>However if you want very good performance you need to use PV network drivers which then provide good performance. I had a 300% improvement in performance, more reliable performance, and reduced cpu load from using those over the emulated nic devices.</i></p>
<p><i>But I guess that PV drivers are only available to people using KVM and not Kqemu/Qemu?</i></p>
<p>PV drivers (ala VirtIO) are now available in upstream QEMU</p>