Re: [kvm-devel] Ubuntu Gutsy host / XP guest / -smp 2

[Avi K. <av...@qu...>]

David Abrahams wrote:
> on Wed Apr 02 2008, Avi Kivity <avi-AT-qumranet.com> wrote:
>
>   
>> David Abrahams wrote:
>>     
>>> With the title combination, the guest takes nearly 100% of my real CPU
>>> time and still only sees one CPU.  Is this a known problem, and does it
>>> have a known solution?
>>>
>>>   
>>>       
>> Can you send the output of 'kvm_stat -1'?  
>>     
>
> $ ./kvm_stat -1
> exits                    5919444     74219
> halt_exits               1746937     59420
> invlpg                         0         0
> io_exits                 2181506      6569
> irq_exits                  23055       335
> irq_window                  2839        77
> mmio_exits                200851         0
> pf_fixed                 1160592      6251
> pf_guest                   43473       396
> request_irq                    0         0
> signal_exits               24838       281
> tlb_flush                  37381      1132
>
>   

Versions of kvm producing this sort of output are common in 
archaeological digs.  Please try a more recent release.

>> What HAL do you see in device manager?
>>     
> "Standard PC"
>
>   

This HAL does not support SMP.  You need the "ACPI Multiprocessor PC" 
HAL or some such.

Unless you have a recent Intel processor, the combination of SMP and 
Windows XP will give noticeably lower performance.  I recommend sticking 
with uniprocessor in such cases.

-- 
Any sufficiently difficult bug is indistinguishable from a feature.