Updated Branches: refs/heads/4.2 2eceb7dcb -> df1756b61
add doc for kvm cpu model Signed-off-by: Wei Zhou <[email protected]> (cherry picked from commit 8d53887cec514e1eeed899e4d6b6465b02aa39a3) Project: http://git-wip-us.apache.org/repos/asf/cloudstack/repo Commit: http://git-wip-us.apache.org/repos/asf/cloudstack/commit/df1756b6 Tree: http://git-wip-us.apache.org/repos/asf/cloudstack/tree/df1756b6 Diff: http://git-wip-us.apache.org/repos/asf/cloudstack/diff/df1756b6 Branch: refs/heads/4.2 Commit: df1756b6197f42abff6a01c55a1b1cbfc9d83eb5 Parents: 2eceb7d Author: JijunLiu <[email protected]> Authored: Mon Aug 12 14:48:08 2013 +0800 Committer: Wei Zhou <[email protected]> Committed: Mon Aug 12 15:35:01 2013 +0200 ---------------------------------------------------------------------- docs/en-US/hypervisor-host-install-agent.xml | 45 ++++++++++++++++++++ .../kvm/resource/LibvirtComputingResource.java | 6 ++- 2 files changed, 49 insertions(+), 2 deletions(-) ---------------------------------------------------------------------- http://git-wip-us.apache.org/repos/asf/cloudstack/blob/df1756b6/docs/en-US/hypervisor-host-install-agent.xml ---------------------------------------------------------------------- diff --git a/docs/en-US/hypervisor-host-install-agent.xml b/docs/en-US/hypervisor-host-install-agent.xml index 41b6719..e339165 100644 --- a/docs/en-US/hypervisor-host-install-agent.xml +++ b/docs/en-US/hypervisor-host-install-agent.xml @@ -31,4 +31,49 @@ <para>In Ubuntu:</para> <programlisting language="Bash"><command>$ apt-get install cloudstack-agent</command></programlisting> <para>The host is now ready to be added to a cluster. This is covered in a later section, see <xref linkend="host-add" />. It is recommended that you continue to read the documentation before adding the host!</para> + <section id="config-cpu-model"> + <title>Configure CPU model for KVM guest (Optional) </title> + <para>In additional,the &PRODUCT; Agent allows host administrator to control the guest CPU model which is exposed to KVM instances. By default, the CPU model of KVM instance is likely <emphasis role="italic"> QEMU Virtual CPU version x.x.x</emphasis> with least CPU features exposed. There are a couple of reasons to specify the CPU model:</para> + <itemizedlist> + <listitem><para>To maximise performance of instances by exposing new host CPU features to the KVM instances;</para> </listitem> + <listitem><para>To ensure a consistent default CPU across all machines,removing reliance of variable QEMU defaults; </para> </listitem> + </itemizedlist> + <para> For the most part it will be sufficient for the host administrator to specify the guest CPU config in the per-host configuration file (/etc/cloudstack/agent/agent.properties). This will be achieved by introducing two new configuration parameters: </para> + <programlisting language="Bash">guest.cpu.mode=custom|host-model|host-passthrough +guest.cpu.model=from /usr/share/libvirt/cpu_map.xml(only valid when guest.cpu.mode=custom) + </programlisting> + <para>There are three choices to fulfill the cpu model changes:</para> + <orderedlist> + <listitem> + <para><emphasis role="bold">custom: </emphasis> you can explicitly specify one of the supported named model in /usr/share/libvirt/cpu_map.xml</para> + </listitem> + <listitem> + <para><emphasis role="bold">host-model: </emphasis> libvirt will identify the CPU model in /usr/share/libvirt/cpu_map.xml which most closely matches the host, and then request additional CPU flags to complete the match. This should give close to maximum functionality/performance, which maintaining good reliability/compatibility if the guest is migrated to another host with slightly different host CPUs. </para> + </listitem> + <listitem> + <para><emphasis role="bold">host-passthrough: </emphasis> libvirt will tell KVM to passthrough the host CPU with no modifications. The difference to host-model, instead of just matching feature flags, every last detail of the host CPU is matched. This gives absolutely best performance, and can be important to some apps which check low level CPU details, but it comes at a cost with respect to migration: the guest can only be migrated to an exactly matching host CPU. </para> + </listitem> + </orderedlist> + <para>Here are some examples:</para> + <itemizedlist> + <listitem> + <para>custom</para> + <programlisting>guest.cpu.mode=custom +guest.cpu.model=SandyBridge + </programlisting> + </listitem> + <listitem> + <para>host-model</para> + <programlisting>guest.cpu.mode=host-model </programlisting> + </listitem> + <listitem> + <para>host-passthrough</para> + <programlisting>guest.cpu.mode=host-passthrough </programlisting> + </listitem> + </itemizedlist> + <note> + <para>host-passthrough may lead to migration failure,if you have this problem,you should use host-model or custom </para> + </note> +</section> + </section> http://git-wip-us.apache.org/repos/asf/cloudstack/blob/df1756b6/plugins/hypervisors/kvm/src/com/cloud/hypervisor/kvm/resource/LibvirtComputingResource.java ---------------------------------------------------------------------- diff --git a/plugins/hypervisors/kvm/src/com/cloud/hypervisor/kvm/resource/LibvirtComputingResource.java b/plugins/hypervisors/kvm/src/com/cloud/hypervisor/kvm/resource/LibvirtComputingResource.java index af3b1f5..5aab7bd 100755 --- a/plugins/hypervisors/kvm/src/com/cloud/hypervisor/kvm/resource/LibvirtComputingResource.java +++ b/plugins/hypervisors/kvm/src/com/cloud/hypervisor/kvm/resource/LibvirtComputingResource.java @@ -771,9 +771,11 @@ ServerResource { if(_hypervisorLibvirtVersion < (9 * 1000 + 10)) { s_logger.warn("LibVirt version 0.9.10 required for guest cpu mode, but version " + prettyVersion(_hypervisorLibvirtVersion) + " detected, so it will be disabled"); - _guestCpuMode = null; - _guestCpuModel = null; + _guestCpuMode = ""; + _guestCpuModel = ""; } + params.put("guest.cpu.mode", _guestCpuMode); + params.put("guest.cpu.model", _guestCpuModel); } String[] info = NetUtils.getNetworkParams(_privateNic);
