Yesterday I tried kvm on my macbook, because I recognized that the cpu does support hardware based virtualization. I wanted to run a virtual machine with the actual kde4 release candidate. First I tried the Suse based KDE4Live, but kvm crashed immediately with “exception 13”. I dunno why that happened, but I didn’t get it working. Then I tried the debian based KDE4-LiveCD which is unfortunately only based on KDE4 beta4. But that cd worked. 🙂
I was just wondering if kvm is quite faster than qemu with kqemu, because it didn’t felt faster. I know that kvm does have a few advantages compared with kqemu, like smp and hardware visualization support, but I asked myself how much faster (or actually slower) would it be compared to kqemu.
So I set up a minimal Debian/testing installation in a qemu image. After that I tried in snapshot mode how long it would last to compile a new standard debian kernel once with kvm and once with kqemu.
But enough words are spoken. Let’s see the facts:
1,83 Ghz Core Duo MacBook as host with kernel 2.6.22-1-686.
The VM got:
– 256 MB RAM
– 2.5GB HDD space
kvm: 30 sec
kqemu: 42 sec
kernel compile time:
kvm: 1h 27min 57sec
kqemu: 2h 13min 17sec
All right. kvm is a lot faster than kqemu, so the reason that it feels not faster on my macbook seems to be the small amount of ram. So I need more ram for my macbook. 😉