Re: [PATCH 2/4] perf stat: Add --for-each-cgroup option

[Namhyung Kim]

On Wed, Sep 16, 2020 at 10:51 PM Arnaldo Carvalho de Melo
<acme@xxxxxxxxxx> wrote:
>
> Em Wed, Sep 16, 2020 at 03:31:27PM +0900, Namhyung Kim escreveu:
> > The --for-each-cgroup option is a syntax sugar to monitor large number
>
> You forgot to add the man page entry for this new option.

OK, will add.. any more comments?

Thanks
Namhyung

>
> > of cgroups easily.  Current command line requires to list all the
> > events and cgroups even if users want to monitor same events for each
> > cgroup.  This patch addresses that usage by copying given events for
> > each cgroup on user's behalf.
> >
> > For instance, if they want to monitor 6 events for 200 cgroups each
> > they should write 1200 event names (with -e) AND 1200 cgroup names
> > (with -G) on the command line.  But with this change, they can just
> > specify 6 events and 200 cgroups with a new option.
> >
> > A simpler example below: It wants to measure 3 events for 2 cgroups
> > ('A' and 'B').  The result is that total 6 events are counted like
> > below.
> >
> >   $ ./perf stat -a -e cpu-clock,cycles,instructions --for-each-cgroup A,B sleep 1
> >
> >    Performance counter stats for 'system wide':
> >
> >               988.18 msec cpu-clock                 A #    0.987 CPUs utilized
> >        3,153,761,702      cycles                    A #    3.200 GHz                      (100.00%)
> >        8,067,769,847      instructions              A #    2.57  insn per cycle           (100.00%)
> >               982.71 msec cpu-clock                 B #    0.982 CPUs utilized
> >        3,136,093,298      cycles                    B #    3.182 GHz                      (99.99%)
> >        8,109,619,327      instructions              B #    2.58  insn per cycle           (99.99%)
> >
> >          1.001228054 seconds time elapsed
> >
> > Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxxx>