Out of curiosity, how are you passing the local storage to the VM? I would also assume a performance hit when using a VM but local storage (instead of Ceph, iscsi, nfs) should still perform well? On Thu, Jan 6, 2022 at 5:44 PM Eric K. Miller <emiller@genesishosting.com> wrote:
no there is no way to enable them out of band of nova today. you technially could wrap the qemu binary wiht a script that inject parmaters but that obviously would not be supported upstream. but that would be a workaround if you really needed it
https://review.opendev.org/c/openstack/devstack/+/817075 is an exmaple of such a script
I created a modified version of your script to wrap the qemu-kvm executable, but when OpenStack starts the VM, Nova returns:
2022-01-06 16:15:24.758 6 ERROR nova.compute.manager libvirtError: internal error: Failed to probe QEMU binary with QMP: qemu-kvm.orig: -object iothread,id=iothread0: invalid option
"-object iothread,id=iothread0" is the first argument.
Our Libvirt/QEMU versions are: Compiled against library: libvirt 4.5.0 Using library: libvirt 4.5.0 Using API: QEMU 4.5.0 Running hypervisor: QEMU 2.12.0
I'm pretty sure these versions includes support for iothreads (for both QEMU as well as Libvirt).
Is Libvirt doing some form of cross-check on the XML parameters with the running QEMU parameters that is incompatible with the wrapper perhaps?
Eric