1 /*
2 * Copyright (c) 2018 The WebRTC project authors. All Rights Reserved.
3 *
4 * Use of this source code is governed by a BSD-style license
5 * that can be found in the LICENSE file in the root of the source
6 * tree. An additional intellectual property rights grant can be found
7 * in the file PATENTS. All contributing project authors may
8 * be found in the AUTHORS file in the root of the source tree.
9 */
10
11 #include "rtc_base/experiments/alr_experiment.h"
12
13 #include <inttypes.h>
14 #include <stdio.h>
15
16 #include <string>
17
18 #include "api/transport/field_trial_based_config.h"
19 #include "rtc_base/logging.h"
20
21 namespace webrtc {
22
23 const char AlrExperimentSettings::kScreenshareProbingBweExperimentName[] =
24 "WebRTC-ProbingScreenshareBwe";
25 const char AlrExperimentSettings::kStrictPacingAndProbingExperimentName[] =
26 "WebRTC-StrictPacingAndProbing";
27 const char kDefaultProbingScreenshareBweSettings[] = "1.0,2875,80,40,-60,3";
28
MaxOneFieldTrialEnabled()29 bool AlrExperimentSettings::MaxOneFieldTrialEnabled() {
30 return AlrExperimentSettings::MaxOneFieldTrialEnabled(
31 FieldTrialBasedConfig());
32 }
33
MaxOneFieldTrialEnabled(const WebRtcKeyValueConfig & key_value_config)34 bool AlrExperimentSettings::MaxOneFieldTrialEnabled(
35 const WebRtcKeyValueConfig& key_value_config) {
36 return key_value_config.Lookup(kStrictPacingAndProbingExperimentName)
37 .empty() ||
38 key_value_config.Lookup(kScreenshareProbingBweExperimentName).empty();
39 }
40
41 absl::optional<AlrExperimentSettings>
CreateFromFieldTrial(const char * experiment_name)42 AlrExperimentSettings::CreateFromFieldTrial(const char* experiment_name) {
43 return AlrExperimentSettings::CreateFromFieldTrial(FieldTrialBasedConfig(),
44 experiment_name);
45 }
46
47 absl::optional<AlrExperimentSettings>
CreateFromFieldTrial(const WebRtcKeyValueConfig & key_value_config,const char * experiment_name)48 AlrExperimentSettings::CreateFromFieldTrial(
49 const WebRtcKeyValueConfig& key_value_config,
50 const char* experiment_name) {
51 absl::optional<AlrExperimentSettings> ret;
52 std::string group_name = key_value_config.Lookup(experiment_name);
53
54 const std::string kIgnoredSuffix = "_Dogfood";
55 std::string::size_type suffix_pos = group_name.rfind(kIgnoredSuffix);
56 if (suffix_pos != std::string::npos &&
57 suffix_pos == group_name.length() - kIgnoredSuffix.length()) {
58 group_name.resize(group_name.length() - kIgnoredSuffix.length());
59 }
60
61 if (group_name.empty()) {
62 if (experiment_name == kScreenshareProbingBweExperimentName) {
63 // This experiment is now default-on with fixed settings.
64 // TODO(sprang): Remove this kill-switch and clean up experiment code.
65 group_name = kDefaultProbingScreenshareBweSettings;
66 } else {
67 return ret;
68 }
69 }
70
71 AlrExperimentSettings settings;
72 if (sscanf(group_name.c_str(), "%f,%" PRId64 ",%d,%d,%d,%d",
73 &settings.pacing_factor, &settings.max_paced_queue_time,
74 &settings.alr_bandwidth_usage_percent,
75 &settings.alr_start_budget_level_percent,
76 &settings.alr_stop_budget_level_percent,
77 &settings.group_id) == 6) {
78 ret.emplace(settings);
79 RTC_LOG(LS_INFO) << "Using ALR experiment settings: "
80 "pacing factor: "
81 << settings.pacing_factor << ", max pacer queue length: "
82 << settings.max_paced_queue_time
83 << ", ALR bandwidth usage percent: "
84 << settings.alr_bandwidth_usage_percent
85 << ", ALR start budget level percent: "
86 << settings.alr_start_budget_level_percent
87 << ", ALR end budget level percent: "
88 << settings.alr_stop_budget_level_percent
89 << ", ALR experiment group ID: " << settings.group_id;
90 } else {
91 RTC_LOG(LS_INFO) << "Failed to parse ALR experiment: " << experiment_name;
92 }
93
94 return ret;
95 }
96
97 } // namespace webrtc
98