Vadim Rozenfeld wrote on 2014-02-14: > On Fri, 2014-02-14 at 02:35 +0000, Liu, RongrongX wrote: >> Vadim Rozenfeld wrote on 2014-02-12: >>> On Wed, 2014-02-12 at 01:33 +0000, Zhang, Yang Z wrote: >>>> Vadim Rozenfeld wrote on 2014-02-10: >>>>> On Mon, 2014-02-10 at 08:21 +0000, Zhang, Yang Z wrote: >>>>>> Hi Vadim, >>>>>> >>>>>> Do you know the latest status of Hyper-v Enlightenments >>>>>> supporting in >>> KVM? >>>>> Like how many Hyper-v interfaces are supported in KVM? >>>>> >>>>> Hi Yang, >>>>> >>>>> There is no many at the moment. KVM currently supports the >>>>> following Hyper-V features: >>>>> >>>>> Guest Spinlocks >>>>> http://msdn.microsoft.com/en-us/library/windows/hardware/ff539 >>>>> 08 >>>>> 1% >>>>> 28v=vs.85%29.aspx >>>>> >>>>> Local APIC MSR Accesses >>>>> http://msdn.microsoft.com/en-us/library/windows/hardware/ff542 >>>>> 39 >>>>> 6% >>>>> 28v=vs.85%29.aspx >>>>> >>>>> Reference Time Counter >>>>> http://msdn.microsoft.com/en-us/library/windows/hardware/ff542 >>>>> 63 >>>>> 7% >>>>> 28v=vs.85%29.aspx >>>>> >>>>> We are going to add: Reference TSC Page >>>>> http://msdn.microsoft.com/en-us/library/windows/hardware/ff542 >>>>> 64 >>>>> 3% >>>>> 28v=vs.85%29.aspx >>>>> >>>>> Lazy EOI support, maybe more. >>>>> >>>> >>>> Thanks for your update. More questions: I want to measure the >>>> performance improvement with hyper-v features enabled. So I want to >>>> know: Are those features enabled by default in KVM? >>> In KVM - yes, but you also need to specify them in QEMU command line. >>> They can be enabled by -cpu features hv_vapic, hv_spinlocks, >>> hv_time, and hv_relaxed >> Hi Vadim, >> in QEMU command line, how to enable these feature? >> I try it with >> 1. [root@vt-snb9 ]#qemu-system-x86_64 -enable-kvm -m 2048 -smp 2 >> -net none win8.1.img -cpu feature >> hv_vapic,+hv_spinlocks,+hv_time,+hv_relaxed >> qemu-system-x86_64: -cpu feature: drive with bus=0, unit=0 >> (index=0) exists 2. [root@vt-snb9]# qemu-system-x86_64 -enable-kvm >> -m 2048 -smp >> 2 -net none win8.1.img -cpu >> qemu64,+hv_vapic,+hv_spinlocks,+hv_time,+hv_relaxed > > something like this: -cpu qemu64, > +x2apic,family=0xf,hv_vapic,hv_spinlocks=0xfff,hv_relaxed,hv_time > > (for hv_vapic we also need x2apic to be enabled)
I saw the win8.1 guest boot up fail with error code 0x0000005c after enabling hv_vapic on my ivy bridge-EP box. But it works well on my Sandy bridge-EP. Any thought? > > Best regards, > Vadim. > >> CPU feature hv_vapic not found >> CPU feature hv_spinlocks not found >> CPU feature hv_time not found >> CPU feature hv_relaxed not found >> CPU feature hv_vapic not found >> CPU feature hv_spinlocks not found >> CPU feature hv_time not found >> CPU feature hv_relaxed not found >> VNC server running on `::1:5900' >> >> >>>> How to turn off/on it manually? >>> Yes. From the QEMU command line. >>> >>>> And how can I know whether guest is using it really? >>> There are two options - printk from the KVM side or WinDbg from >>> the guest side. But in case of hv_time you can check the value >>> returned by QueryPerformanceFrequency >>> http://msdn.microsoft.com/en-us/library/windows/desktop/ms644905% >>> 28v=vs.85%29.aspx >>> it should be 10MHz >>> >>>> Also, Do you have any performance data? >>> http://www.linux-kvm.org/wiki/images/0/0a/2012-forum-kvm_hyperv.pd >>> f >>> pp 16, 18 >>> I compared DPC and ISR times with xperf for two cases - with and >>> without enlightenment. >>> I also have seen reports mentioned around 5-10 percent CPU usage >>> drop on the host side, when loading guest with some disk-stress tests. >>> >>>> >>>>> Kind regards. >>>>> Vadim. >>>>> >>>>>> >>>>>> best regards >>>>>> yang >>>>>> >>>>>> -- >>>>>> To unsubscribe from this list: send the line "unsubscribe kvm" >>>>>> in the body of a message to majord...@vger.kernel.org More >>>>>> majordomo info at http://vger.kernel.org/majordomo-info.html >>>>> >>>>> >>>> >>>> >>>> Best regards, >>>> Yang >>>> >>>> >>> >> > Best regards, Yang
