Re: [RFC][PATCH] KVM: perf: a smart tool to analyse kvm events

[Xiao Guangrong]

On 01/16/2012 06:11 PM, Avi Kivity wrote:


>> Total Samples:975981, Total events handled time:126502464.88us.
> 
> Nice!  If we can have a live version as well, this can replace kvm_stat.
> 
> The average numbers are really high.  Like a factor of 3x-4x off.  Would
> be good to print the standard deviation and see why.  Maybe it's due to
> the tracing overhead.
> 


It is a good suggestion, i will print stddev in the next version.

>> The default event to be analysed is vmexit, we can use --event to specify it,
>> for example, if we want to trace mmio event:
>> # ./perf kvm-events report --event mmio
>>   Warning: Error: expected type 5 but read 4
>>   Warning: Error: expected type 5 but read 0
>>   Warning: unknown op '}'
>>
>>
>> Analyze events for all VCPUs:
>>
>>          MMIO Access    Samples      Samples%         Time%        Avg time
>>
>>         0xfee00380:W     196589        64.95%        70.01%         3.83us
>>         0xfee00310:W      35356        11.68%         6.48%         1.97us
>>         0xfee00300:W      35356        11.68%        16.37%         4.97us
>>         0xfee00300:R      35356        11.68%         7.14%         2.17us
> 
> These are more reasonable (though still high - 5us for an ICR write?)
> 


Hmm, maybe i need look into it...

>> Total Samples:975981, Total events handled time:126502464.88us.
>>
>> I hope guys will like it and any comments are welcome! :)
> 
> I think it's great!  A live version would be a nice addition too.
> 
> Please copy the perf userspace maintainers to get more detailed review
> in the next version.
> 


Okay, Thanks!

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/