Re: [PATCH] perf test: Speed up some tests using perf list

From: Ian Rogers
Date: Wed Oct 16 2024 - 10:55:50 EST


On Wed, Oct 16, 2024 at 1:25 AM James Clark <james.clark@xxxxxxxxxx> wrote:
>
>
>
> On 16/10/2024 7:56 am, Namhyung Kim wrote:
> > On my system, perf list is very slow to print the whole events. I think
> > there's a performance issue in SDT and uprobes event listing. I noticed
> > this issue while running perf test on x86 but it takes long to check
> > some CoreSight event which should be skipped quickly.
> >
> > Anyway, some test uses perf list to check whether the required event is
> > available before running the test. The perf list command can take an
> > argument to specify event class or (glob) pattern. But glob pattern is
> > only to suppress output for unmatched ones after checking all events.
> >
> > In this case, specifying event class is better to reduce the number of
> > events it checks and to avoid buggy subsystems entirely.
> >
> > No functional changes intended.
> >
> > Cc: German Gomez <german.gomez@xxxxxxx>
> > Cc: Carsten Haitzler <carsten.haitzler@xxxxxxx>
> > Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxxx>
> > ---
>
> Reviewed-by: James Clark <james.clark@xxxxxxxxxx>

Reviewed-by: Ian Rogers <irogers@xxxxxxxxxx>

There's a nice better than >2x speed up waiting in too :-)
https://lore.kernel.org/lkml/20241011220354.756798-1-irogers@xxxxxxxxxx/

Thanks,
Ian