More Simulation Framework features

webrtc/modules/remote_bitrate_estimator/test/metric_recorder.cc

+/*
+ *  Copyright (c) 2015 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include "webrtc/modules/remote_bitrate_estimator/test/metric_recorder.h"
+
+#include <algorithm>
+
+namespace webrtc {
+namespace testing {
+namespace bwe {
+
+namespace {
+
+template <typename T>
+T Sum(const std::vector<T>& input) {
+  T total = 0;
+  for (auto it = input.begin(); it != input.end(); ++it) {
+    total += *it;
+  }
+  return total;
+}
+
+template <typename T>
+double Average(const std::vector<T>& array, size_t size) {
+  return static_cast<double>(Sum(array)) / size;
+}
+
+template <typename T>
+std::vector<T> Abs(const std::vector<T>& input) {
+  std::vector<T> output;
+  for (auto it = input.begin(); it != input.end(); ++it) {
+    output.push_back(std::abs(*it));
+  }
+  return output;
+}
+
+template <typename T>
+std::vector<double> Pow(const std::vector<T>& input, double p) {
+  std::vector<double> output;
+  for (auto it = input.begin(); it != input.end(); ++it) {
+    output.push_back(pow(static_cast<double>(*it), p));
+  }
+  return output;
+}
+
+template <typename T>
+double StandardDeviation(const std::vector<T>& array, size_t size) {
+  double mean = Average(array, size);
+  std::vector<double> square_values = Pow(array, 2.0);
+  double var = Average(square_values, size) - mean * mean;
+  return sqrt(var);
+}
+
+// Holder mean, Manhattan distance for p=1, EuclidianNorm/sqrt(n) for p=2.
+template <typename T>
+double NormLp(const std::vector<T>& array, size_t size, double p) {
+  std::vector<T> abs_values = Abs(array);
+  std::vector<double> pow_values = Pow(abs_values, p);
+  return pow(Sum(pow_values) / size, 1.0 / p);
+}
+
+template <typename T>
+std::vector<T> PositiveFilter(const std::vector<T>& input) {
+  std::vector<T> output(input);
+  for (auto it = output.begin(); it != output.end(); ++it) {

[stefan-webrtc, 2015/07/02 11:03:41]

Can't you do this?
for (T val : output)
  val = val > 0 ? val : 0;

Similarly for other loops above and below.

[magalhaesc, 2015/07/02 17:06:18]

Done.

+    (*it) = (*it) > 0 ? (*it) : 0;
+  }
+  return output;
+}
+
+template <typename T>
+std::vector<T> NegativeFilter(const std::vector<T>& input) {
+  std::vector<T> output(input);
+  for (auto it = output.begin(); it != output.end(); ++it) {
+    (*it) = (*it) < 0 ? -(*it) : 0;
+  }
+  return output;
+}
+}  // namespace
+
+MetricRecorder::MetricRecorder(const std::string algorithm_name,
+                               int flow_id,
+                               PacketSender* packet_sender,
+                               ChokeFilter* choke_filter)
+    : algorithm_name_(algorithm_name),
+      flow_id_(flow_id),
+      packet_sender_(packet_sender),
+      choke_filter_(choke_filter),
+      now_ms_(0),
+      delays_ms_(),
+      throughput_bytes_(),
+      weighted_estimate_error_(),
+      last_unweighted_estimate_error_(0),
+      optimal_throughput_bits_(0),
+      last_available_bitrate_per_flow_kbps_(0),
+      start_computing_metrics_ms_(0),
+      started_computing_metrics_(false) {
+  std::fill(last_plot_ms_, last_plot_ms_ + kNumMetrics, 0);
+  std::fill(plot_, plot_ + kNumMetrics, true);
+  plot_[kObjective] = false;
+  plot_[kAvailablePerFlow] = false;
+}
+
+void MetricRecorder::PlotLine(int windows_id,
+                              const std::string& prefix,
+                              int64_t x,
+                              int64_t y) {
+  BWE_TEST_LOGGING_PLOT_WITH_NAME(windows_id, prefix, x, y, algorithm_name_);
+}
+
+void MetricRecorder::PlotThroughput(const std::string& prefix,
+                                    int64_t time_ms,
+                                    int64_t bitrate_kbps) {
+  if (!plot_[kThroughput])
+    return;
+  static const int kThroughputPlotIntervalMs = 100;
+  if (time_ms - last_plot_ms_[kThroughput] > kThroughputPlotIntervalMs) {
+    PlotLine(0, prefix, time_ms, bitrate_kbps);
+    last_plot_ms_[kThroughput] = time_ms;
+  }
+}
+
+void MetricRecorder::PlotDelay(const std::string& prefix,
+                               int64_t time_ms,
+                               int64_t delay_ms) {
+  if (!plot_[kDelay])
+    return;
+  static const int kDelayPlotIntervalMs = 100;
+  if (time_ms - last_plot_ms_[kDelay] > kDelayPlotIntervalMs) {
+    PlotLine(1, prefix, time_ms, delay_ms);
+    last_plot_ms_[kDelay] = time_ms;
+  }
+}
+
+void MetricRecorder::PlotLoss(const std::string& prefix,
+                              int64_t time_ms,
+                              double loss) {
+  if (!plot_[kLoss])
+    return;
+  static const int kPacketLossPlotIntervalMs = 500;
+  if (time_ms - last_plot_ms_[kLoss] > kPacketLossPlotIntervalMs) {
+    PlotLine(2, prefix, time_ms, loss);
+    last_plot_ms_[kLoss] = time_ms;
+  }
+}
+
+void MetricRecorder::PlotObjective(const std::string& prefix, int64_t time_ms) {
+  if (!plot_[kObjective])
+    return;
+  static const int kMetricPlotIntervalMs = 1000;
+  if (time_ms - last_plot_ms_[kObjective] > kMetricPlotIntervalMs) {
+    PlotLine(3, prefix, time_ms, ObjectiveFunction());
+    last_plot_ms_[kObjective] = time_ms;
+  }
+}
+
+void MetricRecorder::PlotTotalAvailableCapacity(const std::string& prefix,
+                                                int64_t time_ms) {
+  if (!plot_[kTotalAvailable])
+    return;
+  static const int kCapacityPlotIntervalMs = 1000;
+  if (time_ms - last_plot_ms_[kTotalAvailable] > kCapacityPlotIntervalMs) {
+    BWE_TEST_LOGGING_PLOT_WITH_NAME(0, prefix, time_ms, GetTotalAvailableKbps(),
+                                    "Available");
+    last_plot_ms_[kTotalAvailable] = time_ms;
+  }
+}
+
+void MetricRecorder::PlotAvailableCapacityPerFlow(const std::string& prefix,
+                                                  int64_t time_ms) {
+  if (!plot_[kAvailablePerFlow])
+    return;
+  static const int kCapacityPlotIntervalMs = 1000;
+  if (time_ms - last_plot_ms_[kAvailablePerFlow] > kCapacityPlotIntervalMs) {
+    BWE_TEST_LOGGING_PLOT_WITH_NAME(
+        0, prefix, time_ms, GetAvailablePerFlowKbps(), "Available_per_flow");
+    last_plot_ms_[kAvailablePerFlow] = time_ms;
+  }
+}
+
+uint32_t MetricRecorder::GetTotalAvailableKbps() {
+  return choke_filter_->TotalAvailableKbps();
+}
+
+uint32_t MetricRecorder::GetAvailablePerFlowKbps() {
+  return choke_filter_->AvailablePerFlowKbps(flow_id_);
+}
+
+uint32_t MetricRecorder::GetSendingEstimateKbps() {
+  return packet_sender_->TargetBitrateKbps();
+}
+
+void MetricRecorder::Update(int64_t time_ms) {
+  now_ms_ = std::max(now_ms_, time_ms);
+  last_available_bitrate_per_flow_kbps_ = GetAvailablePerFlowKbps();
+}
+
+void MetricRecorder::PushDelayMs(int64_t delay_ms, int64_t arrival_time_ms) {
+  if (ShouldRecord(arrival_time_ms)) {
+    delays_ms_.push_back(delay_ms);
+  }
+}
+
+void MetricRecorder::PushThroughputBytes(size_t payload_size,
+                                         int64_t arrival_time_ms) {
+  if (ShouldRecord(arrival_time_ms)) {
+    throughput_bytes_.push_back(payload_size);
+
+    int64_t current_available_per_flow_kbps =
+        static_cast<int64_t>(GetAvailablePerFlowKbps());
+
+    int64_t current_bitrate_diff_kbps =
+        static_cast<int64_t>(GetSendingEstimateKbps()) -
+        current_available_per_flow_kbps;
+
+    // now_ms_ was still not updated here.
+    weighted_estimate_error_.push_back(
+        ((current_bitrate_diff_kbps + last_unweighted_estimate_error_) *
+         (arrival_time_ms - now_ms_)) /
+        2);
+
+    optimal_throughput_bits_ += ((current_available_per_flow_kbps +
+                                  last_available_bitrate_per_flow_kbps_) *
+                                 (arrival_time_ms - now_ms_)) /
+                                2;
+  }
+}
+
+bool MetricRecorder::ShouldRecord(int64_t arrival_time_ms) {
+  if (arrival_time_ms >= start_computing_metrics_ms_) {
+    if (!started_computing_metrics_) {
+      start_computing_metrics_ms_ = arrival_time_ms;
+      now_ms_ = arrival_time_ms;
+      started_computing_metrics_ = true;
+    }
+    return true;
+  } else {
+    return false;
+  }
+}
+
+// The weighted_estimate_error_ was weighted based on time windows.
+// This function scales back the result before plotting.
+double MetricRecorder::Renormalize(double x) {
+  size_t num_packets_received = delays_ms_.size();
+  return (x * num_packets_received) / now_ms_;
+}
+
+inline double U(int64_t x, double alpha) {
+  if (alpha == 1.0) {
+    return log(static_cast<double>(x));
+  }
+  return pow(static_cast<double>(x), 1.0 - alpha) / (1.0 - alpha);
+}
+
+inline double U(size_t x, double alpha) {
+  return U(static_cast<int64_t>(x), alpha);
+}
+
+// TODO(magalhaesc): Update ObjectiveFunction.
+double MetricRecorder::ObjectiveFunction() {
+  const double kDelta = 0.15;  // Delay penalty factor.
+  const double kAlpha = 1.0;
+  const double kBeta = 1.0;
+
+  double throughput_metric = U(Sum(throughput_bytes_), kAlpha);
+  double delay_penalty = kDelta * U(Sum(delays_ms_), kBeta);
+
+  return throughput_metric - delay_penalty;
+}
+
+void MetricRecorder::PlotThroughputHistogram(const std::string& title,
+                                             const std::string& bwe_name,
+                                             int num_flows,
+                                             int64_t extra_offset_ms,
+                                             const std::string optimum_id) {
+  size_t num_packets_received = delays_ms_.size();
+
+  int64_t duration_ms = now_ms_ - start_computing_metrics_ms_ - extra_offset_ms;
+
+  double average_bitrate_kbps =
+      static_cast<double>(8 * Sum(throughput_bytes_) / duration_ms);
+
+  double optimal_bitrate_per_flow_kbps =
+      static_cast<double>(optimal_throughput_bits_ / duration_ms);
+
+  std::vector<int64_t> positive = PositiveFilter(weighted_estimate_error_);
+  std::vector<int64_t> negative = NegativeFilter(weighted_estimate_error_);
+
+  double p_error = Renormalize(NormLp(positive, num_packets_received, 1.0));
+  double n_error = Renormalize(NormLp(negative, num_packets_received, 1.0));
+
+  // Prevent the error to be too close to zero (plotting issue).
+  double extra_error = average_bitrate_kbps / 500;
+
+  std::string optimum_title =
+      optimum_id.empty() ? "optimal_bitrate" : "optimal_bitrates#" + optimum_id;
+
+  BWE_TEST_LOGGING_LABEL(4, title, "average_bitrate_(kbps)", num_flows);
+  BWE_TEST_LOGGING_LIMITERRORBAR(
+      4, bwe_name, average_bitrate_kbps,
+      average_bitrate_kbps - n_error - extra_error,
+      average_bitrate_kbps + p_error + extra_error, "estimate_error",
+      optimal_bitrate_per_flow_kbps, optimum_title, flow_id_);
+
+  // Silencing unused variable compiling error.
+  RTC_UNUSED(p_error);
+  RTC_UNUSED(n_error);
+  RTC_UNUSED(extra_error);
+  RTC_UNUSED(optimal_bitrate_per_flow_kbps);
+}
+
+void MetricRecorder::PlotThroughputHistogram(const std::string& title,
+                                             const std::string& bwe_name,
+                                             int num_flows,
+                                             int64_t extra_offset_ms) {
+  PlotThroughputHistogram(title, bwe_name, num_flows, extra_offset_ms, "");
+}
+
+void MetricRecorder::PlotDelayHistogram(const std::string& title,
+                                        const std::string& bwe_name,
+                                        int num_flows) {
+  size_t num_packets_received = delays_ms_.size();
+  double average_delay_ms = Average(delays_ms_, num_packets_received);
+
+  // Prevent the error to be too close to zero (plotting issue).
+  double extra_error = average_delay_ms / 500;
+
+  double tenth_sigma_ms =
+      StandardDeviation(delays_ms_, num_packets_received) / 10.0 + extra_error;
+
+  BWE_TEST_LOGGING_LABEL(5, title, "average_delay_(ms)", num_flows)
+  BWE_TEST_LOGGING_ERRORBAR(
+      5, bwe_name, average_delay_ms, average_delay_ms - tenth_sigma_ms,
+      average_delay_ms + tenth_sigma_ms, "sigma/10", flow_id_);
+
+  // Silencing unused variable compiling error.
+  RTC_UNUSED(tenth_sigma_ms);
+}
+
+void MetricRecorder::PlotLossHistogram(const std::string& title,
+                                       const std::string& bwe_name,
+                                       int num_flows,
+                                       float global_loss_ratio) {
+  BWE_TEST_LOGGING_LABEL(6, title, "packet_loss_ratio_(%)", num_flows)
+  BWE_TEST_LOGGING_BAR(6, bwe_name, 100.0f * global_loss_ratio, flow_id_);
+}
+
+void MetricRecorder::PlotObjectiveHistogram(const std::string& title,
+                                            const std::string& bwe_name,
+                                            int num_flows) {
+  BWE_TEST_LOGGING_LABEL(7, title, "objective_function", num_flows)
+  BWE_TEST_LOGGING_BAR(7, bwe_name, ObjectiveFunction(), flow_id_);
+}
+
+}  // namespace bwe
+}  // namespace testing
+}  // namespace webrtc