Re: [PATCHv3] perf stat: Ensure group is defined on top of the same cpu mask

From: Jiri Olsa
Date: Tue Jun 02 2020 - 11:28:27 EST


On Tue, Jun 02, 2020 at 12:03:52PM -0300, Arnaldo Carvalho de Melo wrote:

SNIP

> > right, it disables 'grouping', events are scheduled/counted individualy
>
> Ok, I applied this already, we can fix this in the next cycle.
>
> > this way we will not hit the issue when looking for group_fd FD
> > and there's not any, because of different cpu maps
>
> > > If I do:
>
> > > [root@seventh ~]# perf stat -e '{power/energy-cores/,power/energy-ram/},{instructions,cycles}' -a sleep 2
>
> > > Performance counter stats for 'system wide':
>
> > > 1.73 Joules power/energy-cores/
> > > 0.92 Joules power/energy-ram/
> > > 12,191,658 instructions # 0.67 insn per cycles/
> > > 18,275,233 cycles
>
> > > 2.001272492 seconds time elapsed
>
> > > [root@seventh ~]#
> > >
> > > It works, grouped. One observation, shouldn't we somehow show in the
> > > output that the first two were indeed grouped, ditto for the second two?
>
> > yea, we don't display groups in output.. also there's no number
> > for the group, it's still separate events numbers in output
> > grouping is only used when creating events
>
> perhaps if we just add a blank line to separate groups? I.e. the above
> would be:
>
> [root@seventh ~]# perf stat -e '{power/energy-cores/,power/energy-ram/},{instructions,cycles}' -a sleep 2
>
> Performance counter stats for 'system wide':
>
> 1.73 Joules power/energy-cores/
> 0.92 Joules power/energy-ram/
>
> 12,191,658 instructions # 0.67 insn per cycle
> 18,275,233 cycles
>
> 2.001272492 seconds time elapsed

maybe it could be separated by new line and we could put note in the comment:

Performance counter stats for 'system wide':

1.73 Joules power/energy-cores/
0.92 Joules power/energy-ram/ # groupped

12,191,658 instructions # 0.67 insn per cycle
18,275,233 cycles

2.001272492 seconds time elapsed


for events that already have defined comment, it'd be on the next line, like:

Performance counter stats for 'system wide':

1.73 Joules power/energy-cores/
0.92 Joules power/energy-ram/ # XXXXX
# groupped

12,191,658 instructions # 0.67 insn per cycle
18,275,233 cycles

2.001272492 seconds time elapsed


jirka