[PATCH] perf: Util.py add_stats() computes the mean correctly

From: Dima Kogan
Date: Wed Aug 09 2017 - 01:32:14 EST


add_stats() is a utility function for perf scripts to accumulate a value, and
keep track of some statistics. The mean is one of the statistics it keeps track
of, but due to a bug, this wasn't being computed properly. This patch makes the
computation correct

Signed-off-by: Dima Kogan <dima@xxxxxxxxxxxxxxx>
---
tools/perf/scripts/python/Perf-Trace-Util/lib/Perf/Trace/Util.py | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/perf/scripts/python/Perf-Trace-Util/lib/Perf/Trace/Util.py b/tools/perf/scripts/python/Perf-Trace-Util/lib/Perf/Trace/Util.py
index 1d95009592eb..3d1f08b8ba19 100644
--- a/tools/perf/scripts/python/Perf-Trace-Util/lib/Perf/Trace/Util.py
+++ b/tools/perf/scripts/python/Perf-Trace-Util/lib/Perf/Trace/Util.py
@@ -41,7 +41,7 @@ def add_stats(dict, key, value):
min = value
if value > max:
max = value
- avg = (avg + value) / 2
+ avg = (avg*count + float(value)) / (count + 1)
dict[key] = (min, max, avg, count + 1)

def clear_term():
--
2.11.0