| Index: net/quic/congestion_control/rtt_stats.cc
|
| diff --git a/net/quic/congestion_control/rtt_stats.cc b/net/quic/congestion_control/rtt_stats.cc
|
| deleted file mode 100644
|
| index 6c2687df5646ff6c1e3eb5e27f4f4e74367befea..0000000000000000000000000000000000000000
|
| --- a/net/quic/congestion_control/rtt_stats.cc
|
| +++ /dev/null
|
| @@ -1,130 +0,0 @@
|
| -// Copyright 2014 The Chromium Authors. All rights reserved.
|
| -// Use of this source code is governed by a BSD-style license that can be
|
| -// found in the LICENSE file.
|
| -
|
| -#include "net/quic/congestion_control/rtt_stats.h"
|
| -
|
| -#include <complex> // std::abs
|
| -
|
| -using std::max;
|
| -
|
| -namespace net {
|
| -
|
| -namespace {
|
| -
|
| -// Default initial rtt used before any samples are received.
|
| -const int kInitialRttMs = 100;
|
| -const float kAlpha = 0.125f;
|
| -const float kOneMinusAlpha = (1 - kAlpha);
|
| -const float kBeta = 0.25f;
|
| -const float kOneMinusBeta = (1 - kBeta);
|
| -const float kHalfWindow = 0.5f;
|
| -const float kQuarterWindow = 0.25f;
|
| -
|
| -} // namespace
|
| -
|
| -RttStats::RttStats()
|
| - : latest_rtt_(QuicTime::Delta::Zero()),
|
| - min_rtt_(QuicTime::Delta::Zero()),
|
| - smoothed_rtt_(QuicTime::Delta::Zero()),
|
| - mean_deviation_(QuicTime::Delta::Zero()),
|
| - initial_rtt_us_(kInitialRttMs * kNumMicrosPerMilli),
|
| - num_min_rtt_samples_remaining_(0),
|
| - recent_min_rtt_window_(QuicTime::Delta::Infinite()) {}
|
| -
|
| -void RttStats::SampleNewRecentMinRtt(uint32 num_samples) {
|
| - num_min_rtt_samples_remaining_ = num_samples;
|
| - new_min_rtt_ = RttSample();
|
| -}
|
| -
|
| -void RttStats::ExpireSmoothedMetrics() {
|
| - mean_deviation_ =
|
| - max(mean_deviation_,
|
| - QuicTime::Delta::FromMicroseconds(
|
| - std::abs(smoothed_rtt_.Subtract(latest_rtt_).ToMicroseconds())));
|
| - smoothed_rtt_ = max(smoothed_rtt_, latest_rtt_);
|
| -}
|
| -
|
| -// Updates the RTT based on a new sample.
|
| -void RttStats::UpdateRtt(QuicTime::Delta send_delta,
|
| - QuicTime::Delta ack_delay,
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| - QuicTime now) {
|
| - if (send_delta.IsInfinite() || send_delta <= QuicTime::Delta::Zero()) {
|
| - LOG(WARNING) << "Ignoring measured send_delta, because it's is "
|
| - << "either infinite, zero, or negative. send_delta = "
|
| - << send_delta.ToMicroseconds();
|
| - return;
|
| - }
|
| -
|
| - // Update min_rtt_ first. min_rtt_ does not use an rtt_sample corrected for
|
| - // ack_delay but the raw observed send_delta, since poor clock granularity at
|
| - // the client may cause a high ack_delay to result in underestimation of the
|
| - // min_rtt_.
|
| - if (min_rtt_.IsZero() || min_rtt_ > send_delta) {
|
| - min_rtt_ = send_delta;
|
| - }
|
| - UpdateRecentMinRtt(send_delta, now);
|
| -
|
| - // Correct for ack_delay if information received from the peer results in a
|
| - // positive RTT sample. Otherwise, we use the send_delta as a reasonable
|
| - // measure for smoothed_rtt.
|
| - QuicTime::Delta rtt_sample(send_delta);
|
| - if (rtt_sample > ack_delay) {
|
| - rtt_sample = rtt_sample.Subtract(ack_delay);
|
| - }
|
| - latest_rtt_ = rtt_sample;
|
| - // First time call.
|
| - if (smoothed_rtt_.IsZero()) {
|
| - smoothed_rtt_ = rtt_sample;
|
| - mean_deviation_ = QuicTime::Delta::FromMicroseconds(
|
| - rtt_sample.ToMicroseconds() / 2);
|
| - } else {
|
| - mean_deviation_ = QuicTime::Delta::FromMicroseconds(static_cast<int64>(
|
| - kOneMinusBeta * mean_deviation_.ToMicroseconds() +
|
| - kBeta * std::abs(smoothed_rtt_.Subtract(rtt_sample).ToMicroseconds())));
|
| - smoothed_rtt_ = smoothed_rtt_.Multiply(kOneMinusAlpha).Add(
|
| - rtt_sample.Multiply(kAlpha));
|
| - DVLOG(1) << " smoothed_rtt(us):" << smoothed_rtt_.ToMicroseconds()
|
| - << " mean_deviation(us):" << mean_deviation_.ToMicroseconds();
|
| - }
|
| -}
|
| -
|
| -void RttStats::UpdateRecentMinRtt(QuicTime::Delta rtt_sample, QuicTime now) {
|
| - // Recent min_rtt update.
|
| - if (num_min_rtt_samples_remaining_ > 0) {
|
| - --num_min_rtt_samples_remaining_;
|
| - if (new_min_rtt_.rtt.IsZero() || rtt_sample <= new_min_rtt_.rtt) {
|
| - new_min_rtt_ = RttSample(rtt_sample, now);
|
| - }
|
| - if (num_min_rtt_samples_remaining_ == 0) {
|
| - quarter_window_rtt_ = half_window_rtt_ = recent_min_rtt_ = new_min_rtt_;
|
| - }
|
| - }
|
| -
|
| - // Update the three recent rtt samples.
|
| - if (recent_min_rtt_.rtt.IsZero() || rtt_sample <= recent_min_rtt_.rtt) {
|
| - recent_min_rtt_ = RttSample(rtt_sample, now);
|
| - quarter_window_rtt_ = half_window_rtt_ = recent_min_rtt_;
|
| - } else if (rtt_sample <= half_window_rtt_.rtt) {
|
| - half_window_rtt_ = RttSample(rtt_sample, now);
|
| - quarter_window_rtt_ = half_window_rtt_;
|
| - } else if (rtt_sample <= quarter_window_rtt_.rtt) {
|
| - quarter_window_rtt_ = RttSample(rtt_sample, now);
|
| - }
|
| -
|
| - // Expire old min rtt samples.
|
| - if (recent_min_rtt_.time < now.Subtract(recent_min_rtt_window_)) {
|
| - recent_min_rtt_ = half_window_rtt_;
|
| - half_window_rtt_ = quarter_window_rtt_;
|
| - quarter_window_rtt_ = RttSample(rtt_sample, now);
|
| - } else if (half_window_rtt_.time <
|
| - now.Subtract(recent_min_rtt_window_.Multiply(kHalfWindow))) {
|
| - half_window_rtt_ = quarter_window_rtt_;
|
| - quarter_window_rtt_ = RttSample(rtt_sample, now);
|
| - } else if (quarter_window_rtt_.time <
|
| - now.Subtract(recent_min_rtt_window_.Multiply(kQuarterWindow))) {
|
| - quarter_window_rtt_ = RttSample(rtt_sample, now);
|
| - }
|
| -}
|
| -
|
| -} // namespace net
|
|
|