gfe-relnote: In BandwidthSampler, capture the number of lost bytes at the time a packet is sent, and make it available to caller when the packet is acked or lost. No behavior change, not protected.
In addition to the number of lost bytes, this CL also makes the number of sent bytes and number of acked bytes available to caller when a packet is acked or lost.
This is needed for BBRv2 to set inflight_hi when loss is high.
PiperOrigin-RevId: 242001670
Change-Id: I90543435eb1052b2afb3942d1b744c8153524461
diff --git a/quic/core/congestion_control/bandwidth_sampler_test.cc b/quic/core/congestion_control/bandwidth_sampler_test.cc
index e9b74c7..077e9a9 100644
--- a/quic/core/congestion_control/bandwidth_sampler_test.cc
+++ b/quic/core/congestion_control/bandwidth_sampler_test.cc
@@ -4,6 +4,7 @@
#include "net/third_party/quiche/src/quic/core/congestion_control/bandwidth_sampler.h"
+#include "net/third_party/quiche/src/quic/core/quic_types.h"
#include "net/third_party/quiche/src/quic/platform/api/quic_flags.h"
#include "net/third_party/quiche/src/quic/platform/api/quic_test.h"
#include "net/third_party/quiche/src/quic/test_tools/mock_clock.h"
@@ -40,6 +41,10 @@
BandwidthSampler sampler_;
QuicByteCount bytes_in_flight_;
+ QuicByteCount PacketsToBytes(QuicPacketCount packet_count) {
+ return packet_count * kRegularPacketSize;
+ }
+
void SendPacketInner(uint64_t packet_number,
QuicByteCount bytes,
HasRetransmittableData has_retransmittable_data) {
@@ -66,15 +71,19 @@
// Acknowledge receipt of a packet and expect it to be not app-limited.
QuicBandwidth AckPacket(uint64_t packet_number) {
BandwidthSample sample = AckPacketInner(packet_number);
- EXPECT_FALSE(sample.is_app_limited);
+ EXPECT_TRUE(sample.state_at_send.is_valid);
+ EXPECT_FALSE(sample.state_at_send.is_app_limited);
return sample.bandwidth;
}
- void LosePacket(uint64_t packet_number) {
+ SendTimeState LosePacket(uint64_t packet_number) {
QuicByteCount size = BandwidthSamplerPeer::GetPacketSize(
sampler_, QuicPacketNumber(packet_number));
bytes_in_flight_ -= size;
- sampler_.OnPacketLost(QuicPacketNumber(packet_number));
+ SendTimeState send_time_state =
+ sampler_.OnPacketLost(QuicPacketNumber(packet_number));
+ EXPECT_TRUE(send_time_state.is_valid);
+ return send_time_state;
}
// Sends one packet and acks it. Then, send 20 packets. Finally, send
@@ -124,6 +133,63 @@
EXPECT_EQ(0u, bytes_in_flight_);
}
+TEST_F(BandwidthSamplerTest, SendTimeState) {
+ QuicTime::Delta time_between_packets = QuicTime::Delta::FromMilliseconds(10);
+
+ // Send packets 1-5.
+ for (int i = 1; i <= 5; i++) {
+ SendPacket(i);
+ EXPECT_EQ(PacketsToBytes(i), sampler_.total_bytes_sent());
+ clock_.AdvanceTime(time_between_packets);
+ }
+
+ // Ack packet 1.
+ SendTimeState send_time_state = AckPacketInner(1).state_at_send;
+ EXPECT_EQ(PacketsToBytes(1), send_time_state.total_bytes_sent);
+ EXPECT_EQ(0, send_time_state.total_bytes_acked);
+ EXPECT_EQ(0, send_time_state.total_bytes_lost);
+ EXPECT_EQ(PacketsToBytes(1), sampler_.total_bytes_acked());
+
+ // Lose packet 2.
+ send_time_state = LosePacket(2);
+ EXPECT_EQ(PacketsToBytes(2), send_time_state.total_bytes_sent);
+ EXPECT_EQ(0, send_time_state.total_bytes_acked);
+ EXPECT_EQ(0, send_time_state.total_bytes_lost);
+ EXPECT_EQ(PacketsToBytes(1), sampler_.total_bytes_lost());
+
+ // Lose packet 3.
+ send_time_state = LosePacket(3);
+ EXPECT_EQ(PacketsToBytes(3), send_time_state.total_bytes_sent);
+ EXPECT_EQ(0, send_time_state.total_bytes_acked);
+ EXPECT_EQ(0, send_time_state.total_bytes_lost);
+ EXPECT_EQ(PacketsToBytes(2), sampler_.total_bytes_lost());
+
+ // Send packets 6-10.
+ for (int i = 6; i <= 10; i++) {
+ SendPacket(i);
+ EXPECT_EQ(PacketsToBytes(i), sampler_.total_bytes_sent());
+ clock_.AdvanceTime(time_between_packets);
+ }
+
+ // Ack all inflight packets.
+ QuicPacketCount acked_packet_count = 1;
+ EXPECT_EQ(PacketsToBytes(acked_packet_count), sampler_.total_bytes_acked());
+ for (int i = 4; i <= 10; i++) {
+ send_time_state = AckPacketInner(i).state_at_send;
+ ++acked_packet_count;
+ EXPECT_EQ(PacketsToBytes(acked_packet_count), sampler_.total_bytes_acked());
+ EXPECT_EQ(PacketsToBytes(i), send_time_state.total_bytes_sent);
+ if (i <= 5) {
+ EXPECT_EQ(0, send_time_state.total_bytes_acked);
+ EXPECT_EQ(0, send_time_state.total_bytes_lost);
+ } else {
+ EXPECT_EQ(PacketsToBytes(1), send_time_state.total_bytes_acked);
+ EXPECT_EQ(PacketsToBytes(2), send_time_state.total_bytes_lost);
+ }
+ clock_.AdvanceTime(time_between_packets);
+ }
+}
+
// Test the sampler during regular windowed sender scenario with fixed
// CWND of 20.
TEST_F(BandwidthSamplerTest, SendPaced) {
@@ -321,7 +387,7 @@
// app-limited and underestimate the bandwidth due to that.
for (int i = 41; i <= 60; i++) {
BandwidthSample sample = AckPacketInner(i);
- EXPECT_TRUE(sample.is_app_limited);
+ EXPECT_TRUE(sample.state_at_send.is_app_limited);
EXPECT_LT(sample.bandwidth, 0.7f * expected_bandwidth);
SendPacket(i + 20);
