I'm suspecting an issue with nested=1... the nested VM does eventually boot but it takes many minutes to do so. At this point, the cpu usage of qemu-kvm drops to reasonable values. But if you ssh into the vm, the usage jumps up to ~200% again.
To recreate:
$ sudo apt-get install -y genisoimage linux-image-extra-virtual bzr qemu-kvm qemu-utils $ sudo usermod -G kvm -a ubuntu
<logout+back in>
$ sudo modprobe kvm_intel nested=1 $ bzr branch lp:auto-package-testing $ cd auto-package-testing $ bin/prepare-testbed -r saucy -d i386
... and observe ps output.
I'm suspecting an issue with nested=1... the nested VM does eventually boot but it takes many minutes to do so. At this point, the cpu usage of qemu-kvm drops to reasonable values. But if you ssh into the vm, the usage jumps up to ~200% again.
To recreate:
$ sudo apt-get install -y genisoimage linux-image- extra-virtual bzr qemu-kvm qemu-utils
$ sudo usermod -G kvm -a ubuntu
<logout+back in>
$ sudo modprobe kvm_intel nested=1 testing
$ bzr branch lp:auto-package-testing
$ cd auto-package-
$ bin/prepare-testbed -r saucy -d i386
... and observe ps output.