Re: [PATCH 18/20] perf stat: Display event stats using aggr counts

[Jiri Olsa <olsajiri@gmail.com>]

On Wed, Jun 14, 2023 at 09:20:53AM -0700, Ian Rogers wrote:
> On Wed, Jun 14, 2023 at 6:40 AM Jiri Olsa <olsajiri@gmail.com> wrote:
> >
> > On Mon, Oct 17, 2022 at 07:02:25PM -0700, Namhyung Kim wrote:
> > > Now aggr counts are ready for use.  Convert the display routines to use
> > > the aggr counts and update the shadow stat with them.  It doesn't need
> > > to aggregate counts or collect aliases anymore during the display.  Get
> > > rid of now unused struct perf_aggr_thread_value.
> > >
> > > Note that there's a difference in the display order among the aggr mode.
> > > For per-core/die/socket/node aggregation, it shows relevant events in
> > > the same unit together, whereas global/thread/no aggregation it shows
> > > the same events for different units together.  So it still uses separate
> > > codes to display them due to the ordering.
> > >
> > > One more thing to note is that it breaks per-core event display for now.
> > > The next patch will fix it to have identical output as of now.
> > >
> > > Acked-by: Ian Rogers <irogers@google.com>
> > > Signed-off-by: Namhyung Kim <namhyung@kernel.org>
> >
> > hi,
> > this one seems to break 'perf stat -r X' not sure why so far..
> >
> > final counts seems to be accumulated instead of displaying average, like:
> >
> >
> > with this patch:
> >
> >          Performance counter stats for './test_progs -n 103/1' (2 runs):
> >
> >                206,815,929      cycles:u                                                             ( +-  0.05% )
> >             16,052,747,533      cycles:k                                                             ( +-  0.10% )
> >             16,259,643,167      cycles                                                               ( +-  0.10% )
> >
> >                    1.98093 +- 0.00586 seconds time elapsed  ( +-  0.30% )
> >
> >
> > without this patch:
> >
> >          Performance counter stats for './test_progs -n 103/1' (2 runs):
> >
> >                103,300,812      cycles:u                                                             ( +-  0.37% )
> >              8,016,856,866      cycles:k                                                             ( +-  0.32% )
> >              8,120,200,572      cycles                                                               ( +-  0.32% )
> >
> >                    1.97272 +- 0.00270 seconds time elapsed  ( +-  0.14% )
> >
> >
> > any idea? ;-)
> 
> Is this still broken in perf-tools-next? The patch is quite old and
> there's been work in this area. I'm assuming yes, but thought it was
> worth checking.

yes


single run:

	[root@krava perf]# ./perf stat -e cycles:u ./perf bench sched pipe
	# Running 'sched/pipe' benchmark:
	# Executed 1000000 pipe operations between two processes

	     Total time: 4.725 [sec]

	       4.725795 usecs/op
		 211604 ops/sec

	 Performance counter stats for './perf bench sched pipe':

	       398,096,363      cycles:u                                                              

	       4.737638715 seconds time elapsed

	       0.227961000 seconds user
	       4.348895000 seconds sys


3 runs (with verbose):

	[root@krava perf]# ./perf stat -v -r 3 -e cycles:u ./perf bench sched pipe
	Using CPUID GenuineIntel-6-8C-1
	Control descriptor is not initialized
	[ perf stat: executing run #1 ... ]
	# Running 'sched/pipe' benchmark:
	# Executed 1000000 pipe operations between two processes

	     Total time: 4.659 [sec]

	       4.659396 usecs/op
		 214620 ops/sec
	cycles:u: 399150620 3866604490 3866604490
	[ perf stat: executing run #2 ... ]
	# Running 'sched/pipe' benchmark:
	# Executed 1000000 pipe operations between two processes

	     Total time: 4.656 [sec]

	       4.656820 usecs/op
		 214738 ops/sec
	cycles:u: 795910540 7700776638 7700776638
	[ perf stat: executing run #3 ... ]
	# Running 'sched/pipe' benchmark:
	# Executed 1000000 pipe operations between two processes

	     Total time: 4.634 [sec]

	       4.634090 usecs/op
		 215792 ops/sec
	cycles:u: 1189927957 11522039559 11522039559

	 Performance counter stats for './perf bench sched pipe' (3 runs):

	     1,189,927,957      cycles:u                                                                ( +- 19.18% )

		    4.6611 +- 0.0102 seconds time elapsed  ( +-  0.22% )


jirka