Waiman Long mentioned that: Generally speaking, unfair lock performs well for VMs with a small number of vCPUs. Native qspinlock may perform better than pvqspinlock if there is vCPU pinning and there is no vCPU over-commitment. This patchset adds a PV_DEDICATED performance hint to allow hypervisor admin to choose the qspinlock to be used when a dedicated pCPU is available. In addition, according to the original hlt in VMX non-root mode discussion, https://www.spinics.net/lists/kvm/msg152397.html This patchset also adds the per-VM non-HLT-exiting capability to further improve performance under the dedicated pCPU scenarios. Wanpeng Li (2): KVM: X86: Add dedicated pCPU hint PV_DEDICATED KVM: X86: Add per-VM no-HLT-exiting capability Documentation/virtual/kvm/api.txt | 11 +++++++++++ Documentation/virtual/kvm/cpuid.txt | 6 ++++++ arch/x86/include/asm/kvm_host.h | 2 ++ arch/x86/include/uapi/asm/kvm_para.h | 1 + arch/x86/kernel/kvm.c | 6 ++++++ arch/x86/kvm/vmx.c | 21 +++++++++++++++++++++ arch/x86/kvm/x86.c | 5 +++++ arch/x86/kvm/x86.h | 5 +++++ include/uapi/linux/kvm.h | 1 + 9 files changed, 58 insertions(+) -- 2.7.4
