Re: [libvirt] [PATCH v3] qemu: Support numad

numad is an user-level daemon that monitors NUMA topology and processes resource consumption to facilitate good NUMA resource alignment of applications/virtual machines to improve performance and minimize cost of remote memory latencies. It provides a pre-placement advisory interface, so significant processes can be pre-bound to nodes with sufficient available resources. More details: http://fedoraproject.org/wiki/Features/numad "numad -w ncpus:memory_amount" is the advisory interface numad provides currently. This patch add the support by introducing a new XML attribute for <vcpu>. e.g. <vcpu placement="auto">4</vcpu> <vcpu placement="static" cpuset="1-10^6">4</vcpu> The returned advisory nodeset from numad will be printed in domain's dumped XML. e.g. <vcpu placement="auto" cpuset="1-10^6">4</vcpu> If placement is "auto", the number of vcpus and the current memory amount specified in domain XML will be used for numad command line (numad uses MB for memory amount): numad -w $num_of_vcpus:$current_memory_amount / 1024 The advisory nodeset returned from numad will be used to set domain process CPU affinity then. (e.g. qemuProcessInitCpuAffinity). If the user specifies both CPU affinity policy (e.g. (<vcpu cpuset="1-10,^7,^8">4</vcpu>) and placement == "auto" the specified CPU affinity will be overridden. Only QEMU/KVM drivers support it now. See docs update in patch for more details. v2 - v3: * XML schema is changed to <vcpu placement="static|auto">4</vcpu> * Affected tests are updated * LXC driver's support is dropped, let's see what's the real performance on qemu driver first. v1 - v2: * Since Bill Gray says it doesn't matter to use the number of vcpus and current memory amount as numad cmd line argument, though from sementics point of view, what numad expects are physical CPU numbers, let's go this way. v2 dropped XML <cpu required_cpu='4' required_memory='512000'/>, and just a new boolean XML element <autonuma>. Codes are refactored accordingly. * v1 overrides the cpuset specified by <vcpu cpuset='1-10,^7'>2</vcpu>, v2 doesn't do that, but just silently ignored. * xml2xml test is added