Re: high load with win7 & usb tablet

[Avi Kivity <avi@redhat.com>]

  On 09/03/2010 03:21 PM, Michael Tokarev wrote:
> Hello.
>
> I noticed that window7, unlike windowsXP as I played with
> previously, poses quite high load on host when idle.  On
> my machine, host cpu usage is about 25% when one single-cpu
> win7 guest is running with "-usbdevice tablet" option.
> Here's a typical kvm_stats when such a guest is idling:
>
>   efer_reload                  0       0
>   exits                   991832     695
>   fpu_reload                3786       0
>   halt_exits                7759      67
>   halt_wakeup               7717      67
>   host_state_reload       613116     495
>   hypercalls                   0       0
>   insn_emulation          873244     488
>   insn_emulation_fail          0       0
>   invlpg                       0       0
>   io_exits                582925     409
>   irq_exits                30188       8
>   irq_injections           41093       0
>   irq_window                   0       0
>   largepages                 288       0
>   mmio_exits               16718       0
>   mmu_cache_miss             217       0
>   mmu_flooded                  0       0
>   mmu_pde_zapped               0       0
>   mmu_pte_updated              0       0
>   mmu_pte_write                0       0
>   mmu_recycled                 0       0
>   mmu_shadow_zapped          269       0
>   mmu_unsync                   0       0
>   nmi_injections               0       0
>   nmi_window                   0       0
>   pf_fixed                 20630       0
>   pf_guest                     0       0
>   remote_tlb_flush           176       0
>   request_irq                  0       0
>

That's pretty good for an idle guest.

What does the guest think it is doing?  The Windows performance monitor?

-- 

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