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 86eb3abb7e70ae01445cefd113c0d0b6d0bbcca0..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 <cstdlib> // std::abs |
- |
-#include "net/quic/quic_flags.h" |
- |
-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); |
-// 10-second window length for windowed min RTT. |
-const int kMinRttWindowLengthMs = 10000; |
- |
-} // namespace |
- |
-RttStats::RttStats() |
- : latest_rtt_(QuicTime::Delta::Zero()), |
- min_rtt_(QuicTime::Delta::Zero()), |
- smoothed_rtt_(QuicTime::Delta::Zero()), |
- previous_srtt_(QuicTime::Delta::Zero()), |
- mean_deviation_(QuicTime::Delta::Zero()), |
- initial_rtt_us_(kInitialRttMs * kNumMicrosPerMilli), |
- forced_windowed_min_rtt_(QuicTime::Delta::Zero()), |
- forced_windowed_min_rtt_time_(QuicTime::Zero()), |
- num_samples_for_forced_min_(0), |
- windowed_min_rtt_( |
- QuicTime::Delta::FromMilliseconds(kMinRttWindowLengthMs), |
- QuicTime::Delta::Zero(), |
- QuicTime::Zero()) {} |
- |
-void RttStats::SampleNewWindowedMinRtt(uint32_t num_samples) { |
- num_samples_for_forced_min_ = num_samples; |
- forced_windowed_min_rtt_ = QuicTime::Delta::Zero(); |
- forced_windowed_min_rtt_time_ = QuicTime::Zero(); |
-} |
- |
-void RttStats::ExpireSmoothedMetrics() { |
- mean_deviation_ = max(mean_deviation_, |
- QuicTime::Delta::FromMicroseconds(std::abs( |
- (smoothed_rtt_ - 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, |
- 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; |
- } |
- UpdateWindowedMinRtt(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); |
- previous_srtt_ = smoothed_rtt_; |
- |
- if (rtt_sample > ack_delay) { |
- rtt_sample = rtt_sample - 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_t>( |
- kOneMinusBeta * mean_deviation_.ToMicroseconds() + |
- kBeta * std::abs((smoothed_rtt_ - rtt_sample).ToMicroseconds()))); |
- smoothed_rtt_ = kOneMinusAlpha * smoothed_rtt_ + kAlpha * rtt_sample; |
- DVLOG(1) << " smoothed_rtt(us):" << smoothed_rtt_.ToMicroseconds() |
- << " mean_deviation(us):" << mean_deviation_.ToMicroseconds(); |
- } |
-} |
- |
-void RttStats::UpdateWindowedMinRtt(QuicTime::Delta rtt_sample, QuicTime now) { |
- // Update windowed_min_rtt. |
- windowed_min_rtt_.Update(rtt_sample, now); |
- if (num_samples_for_forced_min_ <= 0) { |
- return; |
- } |
- // Reset windowed_min_rtt to the min of num_samples_for_forced_min_ samples. |
- if (forced_windowed_min_rtt_.IsZero() || |
- rtt_sample <= forced_windowed_min_rtt_) { |
- forced_windowed_min_rtt_ = rtt_sample; |
- forced_windowed_min_rtt_time_ = now; |
- } |
- if (num_samples_for_forced_min_ == 1) { |
- windowed_min_rtt_.Reset(forced_windowed_min_rtt_, |
- forced_windowed_min_rtt_time_); |
- } |
- --num_samples_for_forced_min_; |
-} |
- |
-void RttStats::OnConnectionMigration() { |
- 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_samples_for_forced_min_ = 0; |
- windowed_min_rtt_.Reset(QuicTime::Delta::Zero(), QuicTime::Zero()); |
-} |
- |
-} // namespace net |