Re: [PATCH 2/6] perf, tools, stat: Implement CSV metrics output

From: Jiri Olsa
Date: Mon Feb 29 2016 - 05:20:57 EST


On Fri, Feb 26, 2016 at 04:27:57PM -0800, Andi Kleen wrote:
> From: Andi Kleen <ak@xxxxxxxxxxxxxxx>
>
> Now support CSV output for metrics. With the new output callbacks
> this is relatively straight forward by creating new callbacks.
>
> This allows to easily plot metrics from CSV files.
>
> The new line callback needs to know the number of fields to skip them
> correctly
>
> Example output before:
>
> % perf stat -x, true
> 0.200687,,task-clock,200687,100.00
> 0,,context-switches,200687,100.00
> 0,,cpu-migrations,200687,100.00
> 40,,page-faults,200687,100.00
> 730871,,cycles,203601,100.00
> 551056,,stalled-cycles-frontend,203601,100.00
> <not supported>,,stalled-cycles-backend,0,100.00
> 385523,,instructions,203601,100.00
> 78028,,branches,203601,100.00
> 3946,,branch-misses,203601,100.00
>
> After:
>
> % perf stat -x, true
> .502457,,task-clock,502457,100.00,0.485,CPUs utilized
> 0,,context-switches,502457,100.00,0.000,K/sec
> 0,,cpu-migrations,502457,100.00,0.000,K/sec
> 45,,page-faults,502457,100.00,0.090,M/sec
> 644692,,cycles,509102,100.00,1.283,GHz
> 423470,,stalled-cycles-frontend,509102,100.00,65.69,frontend cycles idle
> <not supported>,,stalled-cycles-backend,0,100.00,,,,
> 492701,,instructions,509102,100.00,0.76,insn per cycle
> ,,,,,0.86,stalled cycles per insn
> 97767,,branches,509102,100.00,194.578,M/sec
> 4788,,branch-misses,509102,100.00,4.90,of all branches
>
> or easier readable
>
> perf stat -x, -o x.csv true
> [ak@tassilo hle]$ column -s, -t x.csv
> 0.490635 task-clock 490635 100.00 0.489 CPUs utilized
> 0 context-switches 490635 100.00 0.000 K/sec
> 0 cpu-migrations 490635 100.00 0.000 K/sec
> 45 page-faults 490635 100.00 0.092 M/sec
> 629080 cycles 497698 100.00 1.282 GHz
> 409498 stalled-cycles-frontend 497698 100.00 65.09 frontend cycles idle
> <not supported> stalled-cycles-backend 0 100.00
> 491424 instructions 497698 100.00 0.78 insn per cycle
> 0.83 stalled cycles per insn
> 97278 branches 497698 100.00 198.270 M/sec
> 4569 branch-misses 497698 100.00 4.70 of all branches
>
> Two new fields are added: metric value and metric name.

I'm still getting the empty line:

[jolsa@krava perf]$ ./perf stat -x, true
0.389590,,task-clock,389590,100.00,0.479,CPUs utilized
0,,context-switches,389590,100.00,0.000,K/sec
0,,cpu-migrations,389590,100.00,0.000,K/sec
43,,page-faults,389590,100.00,0.110,M/sec
536038,,cycles,393283,100.00,1.376,GHz
429548,,instructions,393283,100.00,0.80,insn per cycle
,,,,,,,,
85012,,branches,393283,100.00,218.209,M/sec
3600,,branch-misses,393283,100.00,4.23,of all branches

it's not enough just not to include stalled cycles events
in case they are not supported, like you do in patch 1

perf_stat__print_shadow_stats prints stalled cycles
data within instruction event case, so you need to check
for stalled cycles in evlist in there

we have pointer to the evlist in each evsel, so it should be easy

thanks,
jirka