Remove CoDel from webrtc::SimulatedNetwork. This is unused at the moment and webrtc::SimulatedNetwork is going through a refactoring, to keep things simple and well tested this CL removes CoDel but nothing blocks us from re-implementing it when needed. No-Try: True Bug: webrtc:14426 Change-Id: Ie7d40d20a66d3939fc7d3251c47e4f13f3869a27 Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/274407 Reviewed-by: Per Kjellander <perkj@webrtc.org> Auto-Submit: Mirko Bonadei <mbonadei@webrtc.org> Commit-Queue: Erik Språng <sprang@webrtc.org> Reviewed-by: Erik Språng <sprang@webrtc.org> Cr-Commit-Position: refs/heads/main@{#38032}
diff --git a/api/test/simulated_network.h b/api/test/simulated_network.h index fcac51f..fbf5c5c 100644 --- a/api/test/simulated_network.h +++ b/api/test/simulated_network.h
@@ -62,8 +62,6 @@ int avg_burst_loss_length = -1; // Additional bytes to add to packet size. int packet_overhead = 0; - // Enable CoDel active queue management. - bool codel_active_queue_management = false; }; class NetworkBehaviorInterface {
diff --git a/call/BUILD.gn b/call/BUILD.gn index b772f4f..2e24e32 100644 --- a/call/BUILD.gn +++ b/call/BUILD.gn
@@ -645,10 +645,7 @@ rtc_library("fake_network_pipe_unittests") { testonly = true - sources = [ - "fake_network_pipe_unittest.cc", - "simulated_network_unittest.cc", - ] + sources = [ "fake_network_pipe_unittest.cc" ] deps = [ ":fake_network", ":simulated_network",
diff --git a/call/call_factory.cc b/call/call_factory.cc index 066215e..380e80c 100644 --- a/call/call_factory.cc +++ b/call/call_factory.cc
@@ -67,10 +67,6 @@ FieldTrialStructMember( "packet_overhead", [](TimeScopedNetworkConfig* p) { return &p->packet_overhead; }), - FieldTrialStructMember("codel_active_queue_management", - [](TimeScopedNetworkConfig* p) { - return &p->codel_active_queue_management; - }), FieldTrialStructMember( "duration", [](TimeScopedNetworkConfig* p) { return &p->duration; })},
diff --git a/call/simulated_network.cc b/call/simulated_network.cc index fc34fda..f5d0501 100644 --- a/call/simulated_network.cc +++ b/call/simulated_network.cc
@@ -24,62 +24,6 @@ constexpr TimeDelta kDefaultProcessDelay = TimeDelta::Millis(5); } // namespace -CoDelSimulation::CoDelSimulation() = default; -CoDelSimulation::~CoDelSimulation() = default; - -bool CoDelSimulation::DropDequeuedPacket(Timestamp now, - Timestamp enqueing_time, - DataSize packet_size, - DataSize queue_size) { - constexpr TimeDelta kWindow = TimeDelta::Millis(100); - constexpr TimeDelta kDelayThreshold = TimeDelta::Millis(5); - constexpr TimeDelta kDropCountMemory = TimeDelta::Millis(1600); - constexpr DataSize kMaxPacketSize = DataSize::Bytes(1500); - - // Compensates for process interval in simulation; not part of standard CoDel. - TimeDelta queuing_time = now - enqueing_time - kDefaultProcessDelay; - - if (queue_size < kMaxPacketSize || queuing_time < kDelayThreshold) { - enter_drop_state_at_ = Timestamp::PlusInfinity(); - state_ = kNormal; - return false; - } - switch (state_) { - case kNormal: - enter_drop_state_at_ = now + kWindow; - state_ = kPending; - return false; - - case kPending: - if (now >= enter_drop_state_at_) { - state_ = kDropping; - // Starting the drop counter with the drops made during the most recent - // drop state period. - drop_count_ = drop_count_ - previous_drop_count_; - if (now >= last_drop_at_ + kDropCountMemory) - drop_count_ = 0; - previous_drop_count_ = drop_count_; - last_drop_at_ = now; - ++drop_count_; - return true; - } - return false; - - case kDropping: - TimeDelta drop_delay = kWindow / sqrt(static_cast<double>(drop_count_)); - Timestamp next_drop_at = last_drop_at_ + drop_delay; - if (now >= next_drop_at) { - if (queue_size - packet_size < kMaxPacketSize) - state_ = kPending; - last_drop_at_ = next_drop_at; - ++drop_count_; - return true; - } - return false; - } - RTC_CHECK_NOTREACHED(); -} - SimulatedNetwork::SimulatedNetwork(Config config, uint64_t random_seed) : random_(random_seed), bursting_(false) { SetConfig(config); @@ -195,20 +139,6 @@ capacity_link_.pop(); time_us += time_until_front_exits_us; - if (state.config.codel_active_queue_management) { - while (!capacity_link_.empty() && - codel_controller_.DropDequeuedPacket( - Timestamp::Micros(time_us), - Timestamp::Micros(capacity_link_.front().packet.send_time_us), - DataSize::Bytes(capacity_link_.front().packet.size), - DataSize::Bytes(queue_size_bytes_))) { - PacketInfo dropped = capacity_link_.front(); - capacity_link_.pop(); - queue_size_bytes_ -= dropped.packet.size; - dropped.arrival_time_us = PacketDeliveryInfo::kNotReceived; - delay_link_.emplace_back(dropped); - } - } RTC_DCHECK(time_us >= packet.packet.send_time_us); packet.arrival_time_us = std::max(state.pause_transmission_until_us, time_us);
diff --git a/call/simulated_network.h b/call/simulated_network.h index b781b46..d3092ae 100644 --- a/call/simulated_network.h +++ b/call/simulated_network.h
@@ -27,29 +27,6 @@ #include "rtc_base/thread_annotations.h" namespace webrtc { -// Implementation of the CoDel active queue management algorithm. Loosely based -// on CoDel pseudocode from ACMQueue. CoDel keeps queuing delays low by dropping -// packets when delay is high. For each packet ready for dequeue, call -// DropDequeuePacket with the packet parameters to update the CoDel state. -class CoDelSimulation { - public: - CoDelSimulation(); - ~CoDelSimulation(); - - // Returns true if packet should be dropped. - bool DropDequeuedPacket(Timestamp now, - Timestamp enqueing_time, - DataSize packet_size, - DataSize queue_size); - - private: - enum State { kNormal, kPending, kDropping }; - Timestamp enter_drop_state_at_ = Timestamp::PlusInfinity(); - Timestamp last_drop_at_ = Timestamp::MinusInfinity(); - int drop_count_ = 0; - int previous_drop_count_ = 0; - State state_ = State::kNormal; -}; // Class simulating a network link. This is a simple and naive solution just // faking capacity and adding an extra transport delay in addition to the @@ -101,7 +78,6 @@ // `process_checker_` guards the data structures involved in delay and loss // processes, such as the packet queues. rtc::RaceChecker process_checker_; - CoDelSimulation codel_controller_ RTC_GUARDED_BY(process_checker_); std::queue<PacketInfo> capacity_link_ RTC_GUARDED_BY(process_checker_); Random random_;
diff --git a/call/simulated_network_unittest.cc b/call/simulated_network_unittest.cc deleted file mode 100644 index 47b17ca..0000000 --- a/call/simulated_network_unittest.cc +++ /dev/null
@@ -1,149 +0,0 @@ -/* - * Copyright 2019 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 "call/simulated_network.h" - -#include <algorithm> -#include <map> -#include <set> -#include <vector> - -#include "absl/algorithm/container.h" -#include "api/units/data_rate.h" -#include "test/gtest.h" - -namespace webrtc { -namespace { -constexpr int kNotReceived = PacketDeliveryInfo::kNotReceived; -} - -TEST(SimulatedNetworkTest, CodelDoesNothingAtCapacity) { - const TimeDelta kRuntime = TimeDelta::Seconds(30); - - DataRate link_capacity = DataRate::KilobitsPerSec(1000); - const DataSize packet_size = DataSize::Bytes(1000); - - SimulatedNetwork::Config config; - config.codel_active_queue_management = true; - config.queue_delay_ms = 10; - config.link_capacity_kbps = link_capacity.kbps(); - SimulatedNetwork network(config); - - // Need to round up here as otherwise we actually will choke. - const TimeDelta packet_inverval = - packet_size / link_capacity + TimeDelta::Millis(1); - - // Send at capacity and see we get no loss. - Timestamp start_time = Timestamp::Zero(); - Timestamp current_time = start_time; - Timestamp next_packet_time = start_time; - uint64_t next_id = 0; - std::set<uint64_t> pending; - while (current_time - start_time < kRuntime) { - if (current_time >= next_packet_time) { - bool success = network.EnqueuePacket(PacketInFlightInfo{ - packet_size.bytes<size_t>(), current_time.us(), next_id}); - EXPECT_TRUE(success); - pending.insert(next_id); - ++next_id; - next_packet_time += packet_inverval; - } - Timestamp next_delivery = Timestamp::PlusInfinity(); - if (network.NextDeliveryTimeUs()) - next_delivery = Timestamp::Micros(*network.NextDeliveryTimeUs()); - current_time = std::min(next_packet_time, next_delivery); - if (current_time >= next_delivery) { - for (PacketDeliveryInfo packet : - network.DequeueDeliverablePackets(current_time.us())) { - EXPECT_NE(packet.receive_time_us, kNotReceived); - pending.erase(packet.packet_id); - } - } - } - while (network.NextDeliveryTimeUs()) { - for (PacketDeliveryInfo packet : - network.DequeueDeliverablePackets(*network.NextDeliveryTimeUs())) { - EXPECT_NE(packet.receive_time_us, kNotReceived); - pending.erase(packet.packet_id); - } - } - EXPECT_EQ(pending.size(), 0u); -} - -TEST(SimulatedNetworkTest, CodelLimitsDelayAndDropsPacketsOnOverload) { - const TimeDelta kRuntime = TimeDelta::Seconds(30); - const TimeDelta kCheckInterval = TimeDelta::Millis(2000); - - DataRate link_capacity = DataRate::KilobitsPerSec(1000); - const DataSize rough_packet_size = DataSize::Bytes(1500); - const double overload_rate = 1.5; - - SimulatedNetwork::Config config; - config.codel_active_queue_management = true; - config.queue_delay_ms = 10; - config.link_capacity_kbps = link_capacity.kbps(); - SimulatedNetwork network(config); - - const TimeDelta packet_inverval = rough_packet_size / link_capacity; - const DataSize packet_size = overload_rate * link_capacity * packet_inverval; - // Send above capacity and see delays are still controlled at the cost of - // packet loss. - Timestamp start_time = Timestamp::Zero(); - Timestamp current_time = start_time; - Timestamp next_packet_time = start_time; - Timestamp last_check = start_time; - uint64_t next_id = 1; - std::map<uint64_t, int64_t> send_times_us; - int lost = 0; - std::vector<int64_t> delays_us; - while (current_time - start_time < kRuntime) { - if (current_time >= next_packet_time) { - bool success = network.EnqueuePacket(PacketInFlightInfo{ - packet_size.bytes<size_t>(), current_time.us(), next_id}); - send_times_us.insert({next_id, current_time.us()}); - ++next_id; - EXPECT_TRUE(success); - next_packet_time += packet_inverval; - } - Timestamp next_delivery = Timestamp::PlusInfinity(); - if (network.NextDeliveryTimeUs()) - next_delivery = Timestamp::Micros(*network.NextDeliveryTimeUs()); - current_time = std::min(next_packet_time, next_delivery); - if (current_time >= next_delivery) { - for (PacketDeliveryInfo packet : - network.DequeueDeliverablePackets(current_time.us())) { - if (packet.receive_time_us == kNotReceived) { - ++lost; - } else { - delays_us.push_back(packet.receive_time_us - - send_times_us[packet.packet_id]); - } - send_times_us.erase(packet.packet_id); - } - } - if (current_time > last_check + kCheckInterval) { - last_check = current_time; - TimeDelta average_delay = - TimeDelta::Micros(absl::c_accumulate(delays_us, 0)) / - delays_us.size(); - double loss_ratio = static_cast<double>(lost) / (lost + delays_us.size()); - EXPECT_LT(average_delay.ms(), 200) - << "Time " << (current_time - start_time).ms() << "\n"; - EXPECT_GT(loss_ratio, 0.5 * (overload_rate - 1)); - } - } - while (network.NextDeliveryTimeUs()) { - for (PacketDeliveryInfo packet : - network.DequeueDeliverablePackets(*network.NextDeliveryTimeUs())) { - send_times_us.erase(packet.packet_id); - } - } - EXPECT_EQ(send_times_us.size(), 0u); -} -} // namespace webrtc
diff --git a/test/scenario/network_node.cc b/test/scenario/network_node.cc index 702789f..e149bb1 100644 --- a/test/scenario/network_node.cc +++ b/test/scenario/network_node.cc
@@ -28,8 +28,6 @@ sim_config.queue_delay_ms = config.delay.ms(); sim_config.delay_standard_deviation_ms = config.delay_std_dev.ms(); sim_config.packet_overhead = config.packet_overhead.bytes<int>(); - sim_config.codel_active_queue_management = - config.codel_active_queue_management; sim_config.queue_length_packets = config.packet_queue_length_limit.value_or(0); return sim_config;
diff --git a/test/scenario/scenario_config.h b/test/scenario/scenario_config.h index 5ff622f..be0d0b3 100644 --- a/test/scenario/scenario_config.h +++ b/test/scenario/scenario_config.h
@@ -217,7 +217,6 @@ TimeDelta delay = TimeDelta::Zero(); TimeDelta delay_std_dev = TimeDelta::Zero(); double loss_rate = 0; - bool codel_active_queue_management = false; absl::optional<int> packet_queue_length_limit; DataSize packet_overhead = DataSize::Zero(); };