Re: [PATCH 05/11] perf stat: Check existence of frontend/backed stalled cycles
From: Arnaldo Carvalho de Melo
Date: Thu Mar 03 2016 - 07:49:09 EST
Em Thu, Mar 03, 2016 at 09:28:18AM +0100, Ingo Molnar escreveu:
>
> * Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> wrote:
>
> > Before:
> >
> > $ perf stat ls
> > a.patch
> >
> > Performance counter stats for 'ls':
> >
> > 0.822067 task-clock (msec) # 0.873 CPUs utilized (82.26%)
> > 0 context-switches # 0.000 K/sec (82.26%)
> > 0 cpu-migrations # 0.000 K/sec (82.26%)
> > 125 page-faults # 0.152 M/sec (82.26%)
> > 2,516,127 cycles # 3.061 GHz (82.84%)
> > <not supported> stalled-cycles-frontend
> > <not supported> stalled-cycles-backend
> > 2,430,467 instructions # 0.97 insn per cycle (82.84%)
> > 486,235 branches # 591.479 M/sec (82.84%)
> > 18,389 branch-misses # 3.78% of all branches (82.84%)
> >
> > 0.000941536 seconds time elapsed
> > $
> >
> > After:
> >
> > $ perf stat ls
> > a.patch
> >
> > Performance counter stats for 'ls':
> >
> > 0.824919 task-clock (msec) # 0.893 CPUs utilized (85.47%)
> > 0 context-switches # 0.000 K/sec (85.47%)
> > 0 cpu-migrations # 0.000 K/sec (85.47%)
> > 124 page-faults # 0.150 M/sec (85.47%)
> > 2521790 cycles # 3.057 GHz (86.15%)
> > 2364913 instructions # 0.94 insn per cycle (86.15%)
> > 471970 branches # 572.141 M/sec (86.15%)
> > 16935 branch-misses # 3.59% of all branches (86.15%)
> >
> > 0.000923397 seconds time elapsed
> > $
>
> Btw., the output format regression is visible in this changelog already...
Right, uf, should've pick this up at this point :-\
Will go back and fix it up, so that we don't introduce a regression.
- Arnaldo