Re: perf tools miscellaneous questions

From: Reid Kleckner
Date: Wed Nov 03 2010 - 18:15:39 EST


On Wed, Nov 3, 2010 at 5:43 PM, Frederic Weisbecker <fweisbec@xxxxxxxxx> wrote:
>> What's exactly the 'cache-misses' event ? does it include both instructions
>> _and_ data cache misses ? both L1 and L2 caches ?
>>
>> I was expecting so but the following command makes me wondering:
>>
>>   $ perf stat -e cache-misses:u,l1d-loads-misses:u true
>>     Performance counter stats for 'true':
>>
>>                 763  cache-misses
>>                 874  L1-dcache-load-misses
>>
>>         0.000916609  seconds time elapsed
>>
>> Here cache-misses < L1-dcache-load-misses.
>
>
>
> Dunno, will let others answer.

I think it corresponds to last level cache misses, which makes sense
here. The difference in the two numbers represents hits to L2 (and L3
if it exists).

Reid
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