On 06/01/2013 03:16 PM, Dennis Chen wrote:
On 05/29/2013 04:28 AM, Eric Blake wrote:
On 05/28/2013 02:24 PM, Eric Blake wrote:
So the question is: is there any method I can't find yet to change the vcpu count of a running vm dynamically? Wait for newer qemu and libvirt, or else pitch in and help write patches. You might not have to wait that long - if you could help test these patches, it would be appreciated:
https://www.redhat.com/archives/libvir-list/2013-May/msg01857.html
Hi,
After apply the patch, I've made a test. The testing environment as:
virsh # version Compiled against library: libvirt 1.0.5 Using library: libvirt 1.0.5 Using API: QEMU 1.0.5 Running hypervisor: QEMU 1.5.0
The xml piece of the vm domain: <channel type='unix'> <source mode='bind' path='/var/lib/libvirt/qemu/f16x86_64.agent'/> <target type='virtio' name='org.qemu.guest_agent.0'/> </channel>
the network connection between the vm and host is ok.
Also I installed the qemu-guest-agent in the guest os: [root@localhost ~]#rpm -qa | grep qemu-guest qemu-guest-agent-0.12.1.2-2.355.el6.i686
An error happened when I try to offline a guest vcpu in virsh: virsh # setguestvcpu 8 1 --offline error: Guest agent is not responding: Guest agent not available for now
Is there some step I missed before I invoke the 'setguestvcpu' command in virsh or I need to write a program to hot-plug/unplug the vcpu with the help of the new API introduced by this patch? Thanks!
BRs, Dennis
update after investigation, I need to start up the 'qemu-guest-agent' daemon in the guest (https://access.redhat.com/site/documentation/en-US/Red_Hat_Enterprise_Linux/...): [root@localhost ~]#qemu-ga After that, I tried the command again: virsh # setguestvcpu 8 1 --offline error: internal error unable to execute QEMU agent command 'guest-set-vcpus': The command guest-set-vcpus has not been found I think the communication between monitor and guest is ok, because below command is OK: virsh # shutdown 8 --mode agent Domain 8 is being shutdown VM shutdown after this command. Also, I double checked the src/qemu/qemu_agent.c, and I can find the 2 functions: qemuAgentGetVCPUs() and qemuAgentSetVCPUs() Another, virsh # qemu-agent-command 9 '{"execute":"cpu-add","arguments":{"id":2}}' {"error":{"class":"CommandNotFound","desc":"The command cpu-add has not been found","data":{"name":"cpu-add"}}} Seems the guest agent can't find vcpu hot-plug/unplug command, the qemu I am using is 1.5.0, does it need some patches to handle this or something I still missed? BRs, Dennis