compare revision 24a592c2ef586eaffefab068fdf94c284ae80e57 
1#!/usr/bin/env python
2
3import argparse
4import sys
5
6have_scipy = True
7try:
8    import scipy.stats
9except:
10    have_scipy = False
11
12SIGNIFICANCE_THRESHOLD = 0.0001
13
14parser = argparse.ArgumentParser(
15    formatter_class=argparse.RawDescriptionHelpFormatter,
16    description='Compare performance of two runs from nanobench.')
17parser.add_argument('--use_means', action='store_true', default=False,
18                    help='Use means to calculate performance ratios.')
19parser.add_argument('baseline', help='Baseline file.')
20parser.add_argument('experiment', help='Experiment file.')
21args = parser.parse_args()
22
23a,b = {},{}
24for (path, d) in [(args.baseline, a), (args.experiment, b)]:
25    for line in open(path):
26        try:
27            tokens = line.split()
28            if tokens[0] != "Samples:":
29                continue
30            samples  = tokens[1:-1]
31            label    = tokens[-1]
32            d[label] = map(float, samples)
33        except:
34            pass
35
36common = set(a.keys()).intersection(b.keys())
37
38def mean(xs):
39    return sum(xs) / len(xs)
40
41ps = []
42for key in common:
43    p, asem, bsem = 0, 0, 0
44    m = mean if args.use_means else min
45    am, bm = m(a[key]), m(b[key])
46    if have_scipy:
47        _, p = scipy.stats.mannwhitneyu(a[key], b[key])
48        asem, bsem = scipy.stats.sem(a[key]), sem(b[key])
49    ps.append((bm/am, p, key, am, bm, asem, bsem))
50ps.sort(reverse=True)
51
52def humanize(ns):
53    for threshold, suffix in [(1e9, 's'), (1e6, 'ms'), (1e3, 'us'), (1e0, 'ns')]:
54        if ns > threshold:
55            return "%.3g%s" % (ns/threshold, suffix)
56
57maxlen = max(map(len, common))
58
59# We print only signficant changes in benchmark timing distribution.
60bonferroni = SIGNIFICANCE_THRESHOLD / len(ps)  # Adjust for the fact we've run multiple tests.
61for ratio, p, key, am, bm, asem, bsem in ps:
62    if p < bonferroni:
63        str_ratio = ('%.2gx' if ratio < 1 else '%.3gx') % ratio
64        if args.use_means:
65            print '%*s\t%6s(%6s) -> %6s(%6s)\t%s' % (maxlen, key, humanize(am), humanize(asem),
66                                                     humanize(bm), humanize(bsem), str_ratio)
67        else:
68            print '%*s\t%6s -> %6s\t%s' % (maxlen, key, humanize(am), humanize(bm), str_ratio)
69