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* Re: [QUESTION]perf stat: comment of miss ratio
       [not found] <F57F094935A66448B135517D3F6EA397F35063@DGGEMA504-MBS.china.huawei.com>
@ 2019-11-09  2:47 ` Andi Kleen
  2019-11-09  3:19   ` Qi Liu
  2019-11-13 10:45   ` John Garry
  0 siblings, 2 replies; 4+ messages in thread
From: Andi Kleen @ 2019-11-09  2:47 UTC (permalink / raw)
  To: liuqi (BA)
  Cc: linux-kernel, Peter Zijlstra, Ingo Molnar,
	Arnaldo Carvalho de Melo, Mark Rutland, Alexander Shishkin,
	Jiri Olsa, Namhyung Kim, Jin Yao, Ravi Bangoria, Davidlohr Bueso,
	Zhangshaokun, huangdaode, linyunsheng, John Garry

>    Relevant code is checked to make sure that the ratio is calculated by
> 
>    L1-dcache-load-misses/L1-dcache-loads, data "7.58%=30249/399189*100%" also
> 
>    proves this conclusion.
> 
>    So, I'm not sure why we use "of all L1-dcache hits" here to describe miss
>    ratio,

Yes you're right it should be "of all L1-dcache accesses"

Please send a patch to fix the string and also check if this isn't wrong with some other
ratio too.

-Andi

^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: [QUESTION]perf stat: comment of miss ratio
  2019-11-09  2:47 ` [QUESTION]perf stat: comment of miss ratio Andi Kleen
@ 2019-11-09  3:19   ` Qi Liu
  2019-11-09 18:46     ` Andi Kleen
  2019-11-13 10:45   ` John Garry
  1 sibling, 1 reply; 4+ messages in thread
From: Qi Liu @ 2019-11-09  3:19 UTC (permalink / raw)
  To: Andi Kleen
  Cc: linux-kernel, Peter Zijlstra, Ingo Molnar,
	Arnaldo Carvalho de Melo, Mark Rutland, Alexander Shishkin,
	Jiri Olsa, Namhyung Kim, Jin Yao, Ravi Bangoria, Davidlohr Bueso,
	Zhangshaokun, huangdaode, linyunsheng, John Garry



On 2019/11/9 10:47, Andi Kleen wrote:
>>    Relevant code is checked to make sure that the ratio is calculated by
>>
>>    L1-dcache-load-misses/L1-dcache-loads, data "7.58%=30249/399189*100%" also
>>
>>    proves this conclusion.
>>
>>    So, I'm not sure why we use "of all L1-dcache hits" here to describe miss
>>    ratio,
> 
> Yes you're right it should be "of all L1-dcache accesses"
> 
> Please send a patch to fix the string and also check if this isn't wrong with some other
> ratio too.
> 
> -Andi
> 
> .
> 
Hi Andi:
Thanks for your reply firstly.
I check the code and find that "of all...hits" is also used to describe miss ratio of
L1-icache, dTLB cache, iTLB cache, LL-cache. Relevant code as follow:

stat-shadow.c:509:      out->print_metric(config, out->ctx, color, "%7.2f%%", "of all L1-dcache hits", ratio);
stat-shadow.c:530:      out->print_metric(config, out->ctx, color, "%7.2f%%", "of all L1-icache hits", ratio);
stat-shadow.c:550:      out->print_metric(config, out->ctx, color, "%7.2f%%", "of all dTLB cache hits", ratio);
stat-shadow.c:570:      out->print_metric(config, out->ctx, color, "%7.2f%%", "of all iTLB cache hits", ratio);
stat-shadow.c:590:      out->print_metric(config, out->ctx, color, "%7.2f%%", "of all LL-cache hits", ratio);
stat-shadow.c:875:                      print_metric(config, ctxp, NULL, NULL, "of all L1-dcache hits", 0);
stat-shadow.c:885:                      print_metric(config, ctxp, NULL, NULL, "of all L1-icache hits", 0);
stat-shadow.c:895:                      print_metric(config, ctxp, NULL, NULL, "of all dTLB cache hits", 0);
stat-shadow.c:905:                      print_metric(config, ctxp, NULL, NULL, "of all iTLB cache hits", 0);
stat-shadow.c:915:                      print_metric(config, ctxp, NULL, NULL, "of all LL-cache hits", 0);

So, may I send a patch to fix all these strings?

Thanks,
liuqi



^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: [QUESTION]perf stat: comment of miss ratio
  2019-11-09  3:19   ` Qi Liu
@ 2019-11-09 18:46     ` Andi Kleen
  0 siblings, 0 replies; 4+ messages in thread
From: Andi Kleen @ 2019-11-09 18:46 UTC (permalink / raw)
  To: Qi Liu
  Cc: linux-kernel, Peter Zijlstra, Ingo Molnar,
	Arnaldo Carvalho de Melo, Mark Rutland, Alexander Shishkin,
	Jiri Olsa, Namhyung Kim, Jin Yao, Ravi Bangoria, Davidlohr Bueso,
	Zhangshaokun, huangdaode, linyunsheng, John Garry

> So, may I send a patch to fix all these strings?

Yes, probably needed for all of them.

-Andi

^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: [QUESTION]perf stat: comment of miss ratio
  2019-11-09  2:47 ` [QUESTION]perf stat: comment of miss ratio Andi Kleen
  2019-11-09  3:19   ` Qi Liu
@ 2019-11-13 10:45   ` John Garry
  1 sibling, 0 replies; 4+ messages in thread
From: John Garry @ 2019-11-13 10:45 UTC (permalink / raw)
  To: Andi Kleen, liuqi (BA)
  Cc: linux-kernel, Peter Zijlstra, Ingo Molnar,
	Arnaldo Carvalho de Melo, Mark Rutland, Alexander Shishkin,
	Jiri Olsa, Namhyung Kim, Jin Yao, Ravi Bangoria, Davidlohr Bueso,
	Zhangshaokun, huangdaode, linyunsheng

On 09/11/2019 02:47, Andi Kleen wrote:
>>     Relevant code is checked to make sure that the ratio is calculated by
>>
>>     L1-dcache-load-misses/L1-dcache-loads, data "7.58%=30249/399189*100%" also
>>
>>     proves this conclusion.
>>
>>     So, I'm not sure why we use "of all L1-dcache hits" here to describe miss
>>     ratio,
> 
> Yes you're right it should be "of all L1-dcache accesses"
> 
> Please send a patch to fix the string and also check if this isn't wrong with some other
> ratio too.
> 

"    399,189      L1-dcache-loads           #  246.396 M/sec
      30,249      L1-dcache-load-misses     #    7.58% of all L1-dcache 
hits    (18.04%)"


If accesses and loads are equivalent, could we use consistent terminology?

Thanks,
John

^ permalink raw reply	[flat|nested] 4+ messages in thread

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     [not found] <F57F094935A66448B135517D3F6EA397F35063@DGGEMA504-MBS.china.huawei.com>
2019-11-09  2:47 ` [QUESTION]perf stat: comment of miss ratio Andi Kleen
2019-11-09  3:19   ` Qi Liu
2019-11-09 18:46     ` Andi Kleen
2019-11-13 10:45   ` John Garry

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