[PATCH 8/9] perf stat: Display length strings of each run for --table option

From: Jiri Olsa
Date: Mon Apr 23 2018 - 05:09:07 EST


Adding support to display visual aid 'length strings' to
easily spot the biggest difference in time table.

$ perf stat -r 10 --table perf bench sched pipe
...

Performance counter stats for './perf bench sched pipe' (5 runs):

# Table of individual measurements:
5.189 (-0.293) #
5.189 (-0.294) #
5.186 (-0.296) #
5.663 (+0.181) ##
6.186 (+0.703) ####

# Final result:
5.483 +- 0.198 seconds time elapsed ( +- 3.62% )

Suggested-by: Ingo Molnar <mingo@xxxxxxxxxx>
Link: http://lkml.kernel.org/n/tip-hb3t43jryqr4d911yu1ap918@xxxxxxxxxxxxxx
Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
---
tools/perf/builtin-stat.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c
index 345687b0eb10..2137c7d11767 100644
--- a/tools/perf/builtin-stat.c
+++ b/tools/perf/builtin-stat.c
@@ -1759,9 +1759,15 @@ static void print_table(FILE *output, int precision, double avg)

for (idx = 0; idx < run_count; idx++) {
double run = (double) walltime_run[idx] / NSEC_PER_SEC;
+ int h, n = 1 + abs((int) (100.0 * (run - avg)/run) / 5);

- fprintf(output, " %17.*f (%+.*f)\n",
+ fprintf(output, " %17.*f (%+.*f) ",
precision, run, precision, run - avg);
+
+ for (h = 0; h < n; h++)
+ fprintf(output, "#");
+
+ fprintf(output, "\n");
}

fprintf(output, "\n%*s# Final result:\n", indent, "");
--
2.13.6