Re: [RFC PATCH v7 5/6] perf stat: Add retire latency print functions to print out at the very end of print out

[Namhyung Kim]

On Tue, Apr 2, 2024 at 2:46 PM <weilin.wang@xxxxxxxxx> wrote:
>
> From: Weilin Wang <weilin.wang@xxxxxxxxx>
>
> Add print out functions so that users could read retire latency values.
>
> Example output:
>
>  Performance counter stats for 'system wide':
>
>             25,717      MEM_INST_RETIRED.SPLIT_STORES    #      2.2 %  tma_split_stores
>         28,365,080      CPU_CLK_UNHALTED.THREAD
>              24.00      MEM_INST_RETIRED.SPLIT_STORES:p  #       96        4
>
>        2.054365083 seconds time elapsed
>
> This output of retire latency data is in format:
>  <val> <event-name> # <sum> <count>.

Nop, please follow the perf stat output format.  It'd be

  <sum> <event-name> # ...

Hmm.. maybe you don't need this at all as it'll have the event
anyway (probably without the 'p' modifier like in the example
above).

Then I think you can just add a metric value saying the average
latency in the comment area.

  Performance counter stats for 'system wide':

             25,717      MEM_INST_RETIRED.SPLIT_STORES    #      2.2 %
 tma_split_stores
                                                                     #
     24.0  average latency
       28,365,080      CPU_CLK_UNHALTED.THREAD

Thanks,
Namhyung

>
> Signed-off-by: Weilin Wang <weilin.wang@xxxxxxxxx>
> Reviewed-by: Ian Rogers <irogers@xxxxxxxxxx>