2016-02-24 10:32+0000, Avi Cohen: >> Look at last paragraph of my previous email. >> (That one has 1 ns accuracy if KVM is using the masterclock.) > > How to make KVM using the masterclock ? - I don't see any masterclock in traces KVM should use masterclock whenever it can. Host dmesg can contain warning about unstable TSC if masterclock is not being used for good reasons (grep for "TSC unstable" and "unstable TSC"). Relevant tracepoints are (from arch/x86/kvm/trace.h) kvm:kvm_update_master_clock kvm:kvm_track_tsc kvm:kvm_pvclock_update kvm:write_tsc_offset The host is using TSC clocksource, TSC wasn't marked as unstable, guest didn't screw with MSR_IA32_TSC or MSR_IA32_TSC_ADJUST, and masterclock still isn't used? -- 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
