Re: [Valgrind-developers] Strange Cachegrind results

[Nicholas N. <n.n...@gm...>]

On Mon, Nov 9, 2009 at 4:34 AM, Julian Seward <js...@ac...> wrote:
>>
>> Is there a missunderstanding by me?
>
> Yes.  It is true that 7.8% of references presented to the L2 cache miss
> (7.8% == 13820 / 176349).
>
> The L2i miss rate tells you the proportion of instruction
> reads that missed L2, == 2728 / 55537351 == 0.0% as it says.
>
> Similarly for the L2d miss rate.

And the docs (http://www.valgrind.org/docs/manual/cg-manual.html,
section 5.2.1) make this quite clear:

"Note that the L2 miss rate is computed relative to the total number
of memory accesses, not the number of L1 misses. I.e. it is (I2mr +
D2mr + D2mw) / (Ir + Dr + Dw) not (I2mr + D2mr + D2mw) / (I1mr + D1mr
+ D1mw)"

Nick