1 // Copyright 2015 Google Inc. All rights reserved.
2 //
3 // Licensed under the Apache License, Version 2.0 (the "License");
4 // you may not use this file except in compliance with the License.
5 // You may obtain a copy of the License at
6 //
7 // http://www.apache.org/licenses/LICENSE-2.0
8 //
9 // Unless required by applicable law or agreed to in writing, software
10 // distributed under the License is distributed on an "AS IS" BASIS,
11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 // See the License for the specific language governing permissions and
13 // limitations under the License.
14
15 #include "benchmark/reporter.h"
16
17 #include <cstdlib>
18 #include <vector>
19
20 #include "check.h"
21 #include "stat.h"
22
23 namespace benchmark {
24
ComputeStats(const std::vector<Run> & reports,Run * mean_data,Run * stddev_data)25 void BenchmarkReporter::ComputeStats(
26 const std::vector<Run>& reports,
27 Run* mean_data, Run* stddev_data) {
28 CHECK(reports.size() >= 2) << "Cannot compute stats for less than 2 reports";
29 // Accumulators.
30 Stat1_d real_accumulated_time_stat;
31 Stat1_d cpu_accumulated_time_stat;
32 Stat1_d bytes_per_second_stat;
33 Stat1_d items_per_second_stat;
34 // All repetitions should be run with the same number of iterations so we
35 // can take this information from the first benchmark.
36 int64_t const run_iterations = reports.front().iterations;
37
38 // Populate the accumulators.
39 for (Run const& run : reports) {
40 CHECK_EQ(reports[0].benchmark_name, run.benchmark_name);
41 CHECK_EQ(run_iterations, run.iterations);
42 real_accumulated_time_stat +=
43 Stat1_d(run.real_accumulated_time/run.iterations, run.iterations);
44 cpu_accumulated_time_stat +=
45 Stat1_d(run.cpu_accumulated_time/run.iterations, run.iterations);
46 items_per_second_stat += Stat1_d(run.items_per_second, run.iterations);
47 bytes_per_second_stat += Stat1_d(run.bytes_per_second, run.iterations);
48 }
49
50 // Get the data from the accumulator to BenchmarkReporter::Run's.
51 mean_data->benchmark_name = reports[0].benchmark_name + "_mean";
52 mean_data->iterations = run_iterations;
53 mean_data->real_accumulated_time = real_accumulated_time_stat.Mean() *
54 run_iterations;
55 mean_data->cpu_accumulated_time = cpu_accumulated_time_stat.Mean() *
56 run_iterations;
57 mean_data->bytes_per_second = bytes_per_second_stat.Mean();
58 mean_data->items_per_second = items_per_second_stat.Mean();
59
60 // Only add label to mean/stddev if it is same for all runs
61 mean_data->report_label = reports[0].report_label;
62 for (std::size_t i = 1; i < reports.size(); i++) {
63 if (reports[i].report_label != reports[0].report_label) {
64 mean_data->report_label = "";
65 break;
66 }
67 }
68
69 stddev_data->benchmark_name = reports[0].benchmark_name + "_stddev";
70 stddev_data->report_label = mean_data->report_label;
71 stddev_data->iterations = 0;
72 stddev_data->real_accumulated_time =
73 real_accumulated_time_stat.StdDev();
74 stddev_data->cpu_accumulated_time =
75 cpu_accumulated_time_stat.StdDev();
76 stddev_data->bytes_per_second = bytes_per_second_stat.StdDev();
77 stddev_data->items_per_second = items_per_second_stat.StdDev();
78 }
79
Finalize()80 void BenchmarkReporter::Finalize() {
81 }
82
~BenchmarkReporter()83 BenchmarkReporter::~BenchmarkReporter() {
84 }
85
86 } // end namespace benchmark
87