gfe-relnote: In QUIC, add an option PLE2 to arm 1st PTO at least 1.5 * srtt from latest sent packet. Protected by gfe2_reloadable_flag_quic_arm_pto_with_earliest_sent_time.
PiperOrigin-RevId: 298397693
Change-Id: Ia8d65c2f2d68ddf0e669d36e41f9898a4e6787b1
diff --git a/quic/core/quic_sent_packet_manager_test.cc b/quic/core/quic_sent_packet_manager_test.cc
index 4ccb5ca..36d476f 100644
--- a/quic/core/quic_sent_packet_manager_test.cc
+++ b/quic/core/quic_sent_packet_manager_test.cc
@@ -3423,6 +3423,89 @@
manager_.GetRetransmissionTime());
}
+TEST_F(QuicSentPacketManagerTest, ComputingProbeTimeoutByLeftEdge2) {
+ SetQuicReloadableFlag(quic_arm_pto_with_earliest_sent_time, true);
+ EnablePto(k1PTO);
+ // Use PTOS and PLE2.
+ QuicConfig config;
+ QuicTagVector options;
+ options.push_back(kPTOS);
+ options.push_back(kPLE2);
+ QuicConfigPeer::SetReceivedConnectionOptions(&config, options);
+ EXPECT_CALL(*send_algorithm_, SetFromConfig(_, _));
+ EXPECT_CALL(*network_change_visitor_, OnCongestionChange());
+ manager_.SetFromConfig(config);
+ EXPECT_TRUE(manager_.skip_packet_number_for_pto());
+ EXPECT_CALL(*send_algorithm_, CanSend(_)).WillRepeatedly(Return(true));
+ EXPECT_CALL(*send_algorithm_, PacingRate(_))
+ .WillRepeatedly(Return(QuicBandwidth::Zero()));
+ EXPECT_CALL(*send_algorithm_, GetCongestionWindow())
+ .WillRepeatedly(Return(10 * kDefaultTCPMSS));
+ RttStats* rtt_stats = const_cast<RttStats*>(manager_.GetRttStats());
+ rtt_stats->UpdateRtt(QuicTime::Delta::FromMilliseconds(100),
+ QuicTime::Delta::Zero(), QuicTime::Zero());
+ QuicTime::Delta srtt = rtt_stats->smoothed_rtt();
+
+ SendDataPacket(1, ENCRYPTION_FORWARD_SECURE);
+ // Verify PTO is correctly set.
+ QuicTime::Delta expected_pto_delay =
+ srtt + 4 * rtt_stats->mean_deviation() +
+ QuicTime::Delta::FromMilliseconds(kDefaultDelayedAckTimeMs);
+ const QuicTime packet1_sent_time = clock_.Now();
+ EXPECT_EQ(packet1_sent_time + expected_pto_delay,
+ manager_.GetRetransmissionTime());
+
+ // Sent a packet 10ms before PTO expiring.
+ clock_.AdvanceTime(QuicTime::Delta::FromMilliseconds(
+ expected_pto_delay.ToMilliseconds() - 10));
+ SendDataPacket(2, ENCRYPTION_FORWARD_SECURE);
+ // Verify PTO expands to packet 2 sent time + 1.5 * srtt.
+ expected_pto_delay = 1.5 * rtt_stats->smoothed_rtt();
+ EXPECT_EQ(clock_.Now() + expected_pto_delay,
+ manager_.GetRetransmissionTime());
+ EXPECT_EQ(0u, stats_.pto_count);
+
+ // Invoke PTO.
+ clock_.AdvanceTime(expected_pto_delay);
+ manager_.OnRetransmissionTimeout();
+ EXPECT_EQ(QuicTime::Delta::Zero(), manager_.TimeUntilSend(clock_.Now()));
+ EXPECT_EQ(1u, stats_.pto_count);
+
+ EXPECT_CALL(notifier_, RetransmitFrames(_, _))
+ .WillOnce(WithArgs<1>(Invoke([this](TransmissionType type) {
+ RetransmitDataPacket(3, type, ENCRYPTION_FORWARD_SECURE);
+ })));
+ manager_.MaybeSendProbePackets();
+ // Verify PTO period gets set to twice the expected value and based on
+ // packet3 (right edge).
+ expected_pto_delay =
+ srtt + 4 * rtt_stats->mean_deviation() +
+ QuicTime::Delta::FromMilliseconds(kDefaultDelayedAckTimeMs);
+ QuicTime packet3_sent_time = clock_.Now();
+ EXPECT_EQ(packet3_sent_time + expected_pto_delay * 2,
+ manager_.GetRetransmissionTime());
+
+ // Received ACK for packets 1 and 2.
+ uint64_t acked[] = {1, 2};
+ ExpectAcksAndLosses(true, acked, QUICHE_ARRAYSIZE(acked), nullptr, 0);
+ manager_.OnAckFrameStart(QuicPacketNumber(2), QuicTime::Delta::Infinite(),
+ clock_.Now());
+ manager_.OnAckRange(QuicPacketNumber(1), QuicPacketNumber(3));
+ EXPECT_EQ(PACKETS_NEWLY_ACKED,
+ manager_.OnAckFrameEnd(clock_.Now(), QuicPacketNumber(1),
+ ENCRYPTION_FORWARD_SECURE));
+ expected_pto_delay =
+ rtt_stats->SmoothedOrInitialRtt() +
+ std::max(4 * rtt_stats->mean_deviation(),
+ QuicTime::Delta::FromMilliseconds(1)) +
+ QuicTime::Delta::FromMilliseconds(kDefaultDelayedAckTimeMs);
+
+ // Verify PTO is correctly re-armed based on sent time of packet 3 (left
+ // edge).
+ EXPECT_EQ(packet3_sent_time + expected_pto_delay,
+ manager_.GetRetransmissionTime());
+}
+
TEST_F(QuicSentPacketManagerTest,
ComputingProbeTimeoutByLeftEdgeMultiplePacketNumberSpaces) {
SetQuicReloadableFlag(quic_arm_pto_with_earliest_sent_time, true);
@@ -3499,6 +3582,84 @@
manager_.GetRetransmissionTime());
}
+TEST_F(QuicSentPacketManagerTest,
+ ComputingProbeTimeoutByLeftEdge2MultiplePacketNumberSpaces) {
+ SetQuicReloadableFlag(quic_arm_pto_with_earliest_sent_time, true);
+ manager_.EnableMultiplePacketNumberSpacesSupport();
+ EnablePto(k1PTO);
+ // Use PTOS and PLE2.
+ QuicConfig config;
+ QuicTagVector options;
+ options.push_back(kPTOS);
+ options.push_back(kPLE2);
+ QuicConfigPeer::SetReceivedConnectionOptions(&config, options);
+ EXPECT_CALL(*send_algorithm_, SetFromConfig(_, _));
+ EXPECT_CALL(*network_change_visitor_, OnCongestionChange());
+ manager_.SetFromConfig(config);
+ EXPECT_TRUE(manager_.skip_packet_number_for_pto());
+ EXPECT_CALL(*send_algorithm_, CanSend(_)).WillRepeatedly(Return(true));
+ EXPECT_CALL(*send_algorithm_, PacingRate(_))
+ .WillRepeatedly(Return(QuicBandwidth::Zero()));
+ EXPECT_CALL(*send_algorithm_, GetCongestionWindow())
+ .WillRepeatedly(Return(10 * kDefaultTCPMSS));
+ RttStats* rtt_stats = const_cast<RttStats*>(manager_.GetRttStats());
+ rtt_stats->UpdateRtt(QuicTime::Delta::FromMilliseconds(100),
+ QuicTime::Delta::Zero(), QuicTime::Zero());
+ QuicTime::Delta srtt = rtt_stats->smoothed_rtt();
+
+ // Send packet 1.
+ SendDataPacket(1, ENCRYPTION_INITIAL);
+ const QuicTime packet1_sent_time = clock_.Now();
+ // Verify PTO is correctly set.
+ QuicTime::Delta expected_pto_delay =
+ srtt + 4 * rtt_stats->mean_deviation() +
+ QuicTime::Delta::FromMilliseconds(kDefaultDelayedAckTimeMs);
+ EXPECT_EQ(packet1_sent_time + expected_pto_delay,
+ manager_.GetRetransmissionTime());
+
+ // Send packet 2 in handshake.
+ clock_.AdvanceTime(QuicTime::Delta::FromMilliseconds(10));
+ SendDataPacket(2, ENCRYPTION_HANDSHAKE);
+ const QuicTime packet2_sent_time = clock_.Now();
+ // Verify PTO timeout is still based on packet 1.
+ EXPECT_EQ(packet1_sent_time + expected_pto_delay,
+ manager_.GetRetransmissionTime());
+
+ // Discard initial keys.
+ EXPECT_CALL(notifier_, IsFrameOutstanding(_)).WillRepeatedly(Return(false));
+ manager_.NeuterUnencryptedPackets();
+
+ // Send packet 3 in 1-RTT.
+ clock_.AdvanceTime(QuicTime::Delta::FromMilliseconds(10));
+ SendDataPacket(3, ENCRYPTION_FORWARD_SECURE);
+ // Verify PTO timeout is based on packet 2.
+ const QuicTime packet3_sent_time = clock_.Now();
+ EXPECT_EQ(packet2_sent_time + expected_pto_delay,
+ manager_.GetRetransmissionTime());
+
+ // Send packet 4 in handshake.
+ clock_.AdvanceTime(QuicTime::Delta::FromMilliseconds(10));
+ SendDataPacket(4, ENCRYPTION_HANDSHAKE);
+ // Verify PTO timeout is based on packet 4 as application data is ignored.
+ EXPECT_EQ(clock_.Now() + expected_pto_delay,
+ manager_.GetRetransmissionTime());
+
+ // Discard handshake keys.
+ manager_.SetHandshakeConfirmed();
+ // Verify PTO timeout is now based on packet 3 as handshake is
+ // complete/confirmed.
+ EXPECT_EQ(packet3_sent_time + expected_pto_delay,
+ manager_.GetRetransmissionTime());
+
+ // Send packet 5 10ms before PTO expiring.
+ clock_.AdvanceTime(QuicTime::Delta::FromMilliseconds(
+ expected_pto_delay.ToMilliseconds() - 10));
+ SendDataPacket(5, ENCRYPTION_FORWARD_SECURE);
+ // Verify PTO timeout expands to packet 5 sent time + 1.5 * srtt.
+ EXPECT_EQ(clock_.Now() + 1.5 * rtt_stats->smoothed_rtt(),
+ manager_.GetRetransmissionTime());
+}
+
TEST_F(QuicSentPacketManagerTest, SetHandshakeConfirmed) {
QuicSentPacketManagerPeer::SetPerspective(&manager_, Perspective::IS_CLIENT);
manager_.EnableMultiplePacketNumberSpacesSupport();
