Simple implementation of OpenStack Nova Dynamic Add/Remove CPU memory

Environment

Version: RDO OpenStack Liberty

qemu:2.3.0

Libvirt:1.2.17-13

Ideas

Requires qemu-guest-agent support, install the Qemu-guest-agent package in the mirror, set the boot-up, and then mirror the settings metadata:

Both of these options can be set:

Glance image-update <image-id>--property Hw_qemu_guest_agent=yesnova image-meta {image_id} set Hw_qemu_guest_ Agent=yes

The resulting virtual machine libvirt XML file will then be the following information:

<channel type= ' unix ' > <source mode= ' bind ' path= '/var/lib/libvirt/qemu/org.qemu.guest_ Agent.0.instance-00000011.sock '/> <target type= ' virtio ' name= ' org.qemu.guest_agent.0 '/> <address type= ' Virtio-serial ' controller= ' 0 ' bus= ' 0 ' port= ' 1 '/></channel>

1, Hot add CPU function: Libvirt interface support, by configuring the Nova flavor meta-data Cpu:max to pre-allocate vcpus, and finally call Libvirt Setvcpusflags function to implement (note: Hard restart virtual machine, Libvirt The XML file is regenerated based on the information in the database table, which has been processed.

2, heat removal CPU function: After removing the Vcpus, the virtual machine needs to be restarted (this can be set at the end of the API limit, can be removed from the VM operation)

3, hot add, heat reduce memory: this seems to be no problem, set the maximum memory, libvirt that there can not be active domain

This is my simple implementation: https://github.com/yaoice/nova/commit/26e9e3840abc0f8c81342b58c14c5af0e397c063

Test

Token= ' OpenStack token issue | awk '/id/{print $4} ' | Head-1 ' export token=${token}export server= ' Nova list | awk '/active/{print $} '

Show Virtual machine Vcpus number

Curl-i "http://node_172_16_214_226:8774/v2.1/7d58dea58dd448d4b095da27986176f2/servers/${server}/ Os-server-cpu-hotplug "-X get-h" User-agent:python-novaclient "-H" content-type:application/jso N "-H" accept:application/json "-H" X-auth-token: ${token} "

Set up virtual machine Vcpus

Curl-g-i-x POST http://node_172_16_214_226:8774/v2.1/7d58dea58dd448d4b095da27986176f2/servers/${server}/action         -H "user-agent:python-novaclient"-H "content-type:application/json"-H "Accept:application/json" -H "x-openstack-nova-api-version:2.5"-H "X-auth-token: ${token}"-d ' {"Setvcpus": {"Vcpus": 6}} '

The Libvirt XML for setting up a successful virtual machine has the following information:

Libvirt vcpus xml: <vcpu placement= ' static ' current= ' 4 ' >16</vcpu>

Displaying the memory of a virtual machine

Curl-i "http://node_172_16_214_226:8774/v2.1/7d58dea58dd448d4b095da27986176f2/servers/${server}/ Os-server-mem-hottune "-X get-h" User-agent:python-novaclient "-H" content-type:application/jso N "-H" accept:application/json "-H" X-auth-token: ${token} "

Set the memory for a virtual machine

Curl-g-i-x POST http://node_172_16_214_226:8774/v2.1/7d58dea58dd448d4b095da27986176f2/servers/${server}/action         -H "user-agent:python-novaclient"-H "content-type:application/json"-H "Accept:application/json" -H "x-openstack-nova-api-version:2.5"-H "X-auth-token: ${token}"-d ' {"Setmem": {"mem": 4096}} '

Common error

Virsh # Setvcpus--live--guest instance-00000040 3error:invalid argument:requested vcpus count is greater than the count of enabled Vcpus in the Domain:3 > 2virsh # setmaxmem--live one 7292608error:unable to change maxmemorysizeerror:re Quested operation isn't valid:cannot resize the maximum memory on active domain

Reference links

(How to add Nova API method) https://github.com/accelazh/example-nova-exensions/blob/master/nova/nova/api/openstack/ compute/contrib/example_resource.py

(How to configure Qemu-guest-agent) https://www.sebastien-han.fr/blog/2015/02/09/ openstack-perform-consistent-snapshots-with-qemu-guest-agent/

(Flavor extra_specs usage) http://docs.openstack.org/admin-guide/compute-flavors.html

(KVM host dynamically changes CPU count and memory size) http://bbotte.blog.51cto.com/6205307/1635733

(Libvirt CPU Hot Remove will need to restart the number of CPUs to really reduce) http://www.unixarena.com/2015/12/ Linux-kvm-how-to-add-remove-vcpu-to-guest-on-fly.html

This article is from the "The-way-to-cloud" blog, make sure to keep this source http://iceyao.blog.51cto.com/9426658/1879601

Simple implementation of OpenStack Nova Dynamic Add/Remove CPU memory