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Removing the TFRC Rate Control

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This removes the TRFC rate control which does not introduce any help in the
computation of the sending rate.
BUG=5083

Review URL: https://codereview.webrtc.org/1383813003

Cr-Commit-Position: refs/heads/master@{#10299}
This commit is contained in:
gaetano.carlucci 2015-10-16 02:52:22 -07:00 committed by Commit bot
parent 949c2f04b4
commit 757077b34e
1 changed files with 0 additions and 30 deletions
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30
webrtc/modules/bitrate_controller/send_side_bandwidth_estimation.cc
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@ -24,7 +24,6 @@ const int64_t kBweDecreaseIntervalMs = 300;
const int64_t kStartPhaseMs = 2000;
const int64_t kBweConverganceTimeMs = 20000;
const int kLimitNumPackets = 20;
const int kAvgPacketSizeBytes = 1000;
const int kDefaultMinBitrateBps = 10000;
const int kDefaultMaxBitrateBps = 1000000000;
const int64_t kLowBitrateLogPeriodMs = 10000;
@ -41,29 +40,6 @@ const UmaRampUpMetric kUmaRampupMetrics[] = {
const size_t kNumUmaRampupMetrics =
sizeof(kUmaRampupMetrics) / sizeof(kUmaRampupMetrics[0]);
// Calculate the rate that TCP-Friendly Rate Control (TFRC) would apply.
// The formula in RFC 3448, Section 3.1, is used.
uint32_t CalcTfrcBps(int64_t rtt, uint8_t loss) {
if (rtt == 0 || loss == 0) {
// Input variables out of range.
return 0;
}
double R = static_cast<double>(rtt) / 1000; // RTT in seconds.
int b = 1; // Number of packets acknowledged by a single TCP acknowledgement:
// recommended = 1.
double t_RTO = 4.0 * R; // TCP retransmission timeout value in seconds
// recommended = 4*R.
double p = static_cast<double>(loss) / 255; // Packet loss rate in [0, 1).
double s = static_cast<double>(kAvgPacketSizeBytes);
// Calculate send rate in bytes/second.
double X =
s / (R * std::sqrt(2 * b * p / 3) +
(t_RTO * (3 * std::sqrt(3 * b * p / 8) * p * (1 + 32 * p * p))));
// Convert to bits/second.
return (static_cast<uint32_t>(X * 8));
}
}
SendSideBandwidthEstimation::SendSideBandwidthEstimation()
@ -245,12 +221,6 @@ void SendSideBandwidthEstimation::UpdateEstimate(int64_t now_ms) {
bitrate_ = static_cast<uint32_t>(
(bitrate_ * static_cast<double>(512 - last_fraction_loss_)) /
512.0);
// Calculate what rate TFRC would apply in this situation and to not
// reduce further than it.
bitrate_ = std::max(
bitrate_,
CalcTfrcBps(last_round_trip_time_ms_, last_fraction_loss_));
}
}
}