Re: [PATCH v4 2/3] perf stat: Add JSON output option

[Namhyung Kim]

Hi Ian,

On Tue, May 24, 2022 at 10:38 PM Ian Rogers <irogers@xxxxxxxxxx> wrote:
>
> From: Claire Jensen <cjense@xxxxxxxxxx>
>
> CSV output is tricky to format and column layout changes are susceptible
> to breaking parsers. New JSON-formatted output has variable names to
> identify fields that are consistent and informative, making
> the output parseable.
>
> CSV output example:
>
> 1.20,msec,task-clock:u,1204272,100.00,0.697,CPUs utilized
> 0,,context-switches:u,1204272,100.00,0.000,/sec
> 0,,cpu-migrations:u,1204272,100.00,0.000,/sec
> 70,,page-faults:u,1204272,100.00,58.126,K/sec
>
> JSON output example:
>
> {"counter-value" : "3805.723968", "unit" : "msec", "event" :
> "cpu-clock", "event-runtime" : 3805731510100.00, "pcnt-running"
> : 100.00, "metric-value" : 4.007571, "metric-unit" : "CPUs utilized"}
> {"counter-value" : "6166.000000", "unit" : "", "event" :
> "context-switches", "event-runtime" : 3805723045100.00, "pcnt-running"
> : 100.00, "metric-value" : 1.620191, "metric-unit" : "K/sec"}
> {"counter-value" : "466.000000", "unit" : "", "event" :
> "cpu-migrations", "event-runtime" : 3805727613100.00, "pcnt-running"
> : 100.00, "metric-value" : 122.447136, "metric-unit" : "/sec"}
> {"counter-value" : "208.000000", "unit" : "", "event" :
> "page-faults", "event-runtime" : 3805726799100.00, "pcnt-running"
> : 100.00, "metric-value" : 54.654516, "metric-unit" : "/sec"}
>
> Also added documentation for JSON option.
> There is some tidy up of CSV code including a potential memory over run
> in the os.nfields set up. To facilitate this an AGGR_MAX value is added.
>
> Signed-off-by: Claire Jensen <cjense@xxxxxxxxxx>

Your sign-off as well?

Anyway, I think there are places to clean up this part of code
more but that's not a part of the work.  Maybe I need to find
some time to do that later.

Acked-by: Namhyung Kim <namhyung@xxxxxxxxxx>

Thanks,
Namhyung