2016-10-13 19:34 GMT+08:00 Wanpeng Li <kernellwp@xxxxxxxxx>: [...] > > The patchset reduces ~300+ clock cycles for each APIC timer oneshot mode > operation virtualization. However, the performance of periodic mode is > still bad, so this version is still a RFC. Your comments to improve the > patchset is a great appreciated. I observed that the clock cycles between the start of kvm_lapic_expired_hv_timer() (periodic mode emulated through restart a preemption timer after the last preemption timer vmexit) to kvm_inject_apic_timer_irqs() is almost half of the clock cycles between the start of apic_timer_fn() (periodic mode emulated through hrtimer) to kvm_inject_apic_timers_irqs(), so the overhead of preemption timer is lower in this path. Maybe something is still not correct in other places which results in performance of periodic mode emulated by VMX preemption timer is still not good. Any help is a great appreciated. :) Radim, Paolo, ping :) Regards, Wanpeng Li -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
