Default to 2 * RTTVAR when calculating PTO delay.
Protected by FLAGS_quic_reloadable_flag_quic_default_to_2_rttvar.
PiperOrigin-RevId: 333118367
Change-Id: I1d71f13327767deb512dfdabbe0cb612437c0041
diff --git a/quic/core/quic_sent_packet_manager.cc b/quic/core/quic_sent_packet_manager.cc
index ab43af3..f453619 100644
--- a/quic/core/quic_sent_packet_manager.cc
+++ b/quic/core/quic_sent_packet_manager.cc
@@ -957,6 +957,10 @@
max_probe_packets_per_pto_ = 1;
skip_packet_number_for_pto_ = true;
first_pto_srtt_multiplier_ = 1.5;
+ if (GetQuicReloadableFlag(quic_default_to_2_rttvar)) {
+ QUIC_RELOADABLE_FLAG_COUNT(quic_default_to_2_rttvar);
+ pto_rttvar_multiplier_ = 2;
+ }
}
void QuicSentPacketManager::StartExponentialBackoffAfterNthPto(
diff --git a/quic/core/quic_sent_packet_manager_test.cc b/quic/core/quic_sent_packet_manager_test.cc
index dfc5b86..c186f65 100644
--- a/quic/core/quic_sent_packet_manager_test.cc
+++ b/quic/core/quic_sent_packet_manager_test.cc
@@ -335,6 +335,17 @@
EXPECT_TRUE(manager_.pto_enabled());
}
+ int GetPtoRttvarMultiplier() {
+ if (GetQuicReloadableFlag(quic_default_on_pto)) {
+ return 2;
+ }
+ if (GetQuicReloadableFlag(quic_default_to_2_rttvar) &&
+ manager_.handshake_mode_disabled()) {
+ return 2;
+ }
+ return 4;
+ }
+
SimpleBufferAllocator allocator_;
QuicSentPacketManager manager_;
MockClock clock_;
@@ -2643,10 +2654,8 @@
SendDataPacket(1, ENCRYPTION_FORWARD_SECURE);
// Verify PTO is correctly set.
- int pto_rttvar_multiplier =
- GetQuicReloadableFlag(quic_default_on_pto) ? 2 : 4;
QuicTime::Delta expected_pto_delay =
- srtt + pto_rttvar_multiplier * rtt_stats->mean_deviation() +
+ srtt + GetPtoRttvarMultiplier() * rtt_stats->mean_deviation() +
QuicTime::Delta::FromMilliseconds(kDefaultDelayedAckTimeMs);
QuicTime packet1_sent_time = clock_.Now();
EXPECT_EQ(clock_.Now() + expected_pto_delay,
@@ -2696,7 +2705,7 @@
ENCRYPTION_FORWARD_SECURE));
expected_pto_delay =
rtt_stats->SmoothedOrInitialRtt() +
- std::max(pto_rttvar_multiplier * rtt_stats->mean_deviation(),
+ std::max(GetPtoRttvarMultiplier() * rtt_stats->mean_deviation(),
QuicTime::Delta::FromMilliseconds(1)) +
QuicTime::Delta::FromMilliseconds(kDefaultDelayedAckTimeMs);
@@ -2722,10 +2731,8 @@
QuicTime::Delta::Zero(), QuicTime::Zero());
QuicTime::Delta srtt = rtt_stats->smoothed_rtt();
// Verify PTO period is correctly set.
- int pto_rttvar_multiplier =
- GetQuicReloadableFlag(quic_default_on_pto) ? 2 : 4;
QuicTime::Delta expected_pto_delay =
- srtt + pto_rttvar_multiplier * rtt_stats->mean_deviation() +
+ srtt + GetPtoRttvarMultiplier() * rtt_stats->mean_deviation() +
QuicTime::Delta::FromMilliseconds(kDefaultDelayedAckTimeMs);
QuicTime deadline = clock_.Now() + expected_pto_delay;
if (GetQuicReloadableFlag(quic_default_on_pto)) {
@@ -2828,10 +2835,8 @@
SendDataPacket(1, ENCRYPTION_FORWARD_SECURE);
QuicTime packet1_sent_time = clock_.Now();
// Verify PTO is correctly set and ack delay is included.
- int pto_rttvar_multiplier =
- GetQuicReloadableFlag(quic_default_on_pto) ? 2 : 4;
QuicTime::Delta expected_pto_delay =
- srtt + pto_rttvar_multiplier * rtt_stats->mean_deviation() +
+ srtt + GetPtoRttvarMultiplier() * rtt_stats->mean_deviation() +
QuicTime::Delta::FromMilliseconds(kDefaultDelayedAckTimeMs);
EXPECT_EQ(clock_.Now() + expected_pto_delay,
manager_.GetRetransmissionTime());
@@ -2878,7 +2883,7 @@
ENCRYPTION_FORWARD_SECURE));
expected_pto_delay =
rtt_stats->SmoothedOrInitialRtt() +
- std::max(pto_rttvar_multiplier * rtt_stats->mean_deviation(),
+ std::max(GetPtoRttvarMultiplier() * rtt_stats->mean_deviation(),
QuicTime::Delta::FromMilliseconds(1)) +
QuicTime::Delta::FromMilliseconds(kDefaultDelayedAckTimeMs);
@@ -2912,7 +2917,7 @@
expected_pto_delay =
rtt_stats->SmoothedOrInitialRtt() +
- std::max(pto_rttvar_multiplier * rtt_stats->mean_deviation(),
+ std::max(GetPtoRttvarMultiplier() * rtt_stats->mean_deviation(),
QuicTime::Delta::FromMilliseconds(1)) +
QuicTime::Delta::FromMilliseconds(kDefaultDelayedAckTimeMs);
for (size_t i = 101; i < 110; i++) {
@@ -2952,10 +2957,8 @@
SendDataPacket(1, ENCRYPTION_FORWARD_SECURE);
QuicTime packet1_sent_time = clock_.Now();
// Verify PTO is correctly set.
- int pto_rttvar_multiplier =
- GetQuicReloadableFlag(quic_default_on_pto) ? 2 : 4;
QuicTime::Delta expected_pto_delay =
- srtt + pto_rttvar_multiplier * rtt_stats->mean_deviation() +
+ srtt + GetPtoRttvarMultiplier() * rtt_stats->mean_deviation() +
QuicTime::Delta::FromMilliseconds(kDefaultDelayedAckTimeMs);
EXPECT_EQ(packet1_sent_time + expected_pto_delay,
manager_.GetRetransmissionTime());
@@ -3163,10 +3166,8 @@
// Verify PTO period gets set correctly.
QuicTime sent_time = clock_.Now();
- int pto_rttvar_multiplier =
- GetQuicReloadableFlag(quic_default_on_pto) ? 2 : 4;
expected_pto_delay =
- srtt + pto_rttvar_multiplier * rtt_stats->mean_deviation() +
+ srtt + GetPtoRttvarMultiplier() * rtt_stats->mean_deviation() +
QuicTime::Delta::FromMilliseconds(kDefaultDelayedAckTimeMs);
EXPECT_EQ(sent_time + expected_pto_delay * 2,
manager_.GetRetransmissionTime());
@@ -3227,10 +3228,8 @@
RetransmitDataPacket(5, type, ENCRYPTION_FORWARD_SECURE);
})));
manager_.MaybeSendProbePackets();
- int pto_rttvar_multiplier =
- GetQuicReloadableFlag(quic_default_on_pto) ? 2 : 4;
expected_pto_delay =
- srtt + pto_rttvar_multiplier * rtt_stats->mean_deviation() +
+ srtt + GetPtoRttvarMultiplier() * rtt_stats->mean_deviation() +
QuicTime::Delta::FromMilliseconds(kDefaultDelayedAckTimeMs);
// Verify PTO period gets set correctly.
@@ -3267,10 +3266,8 @@
// Send packet 1.
SendDataPacket(1, ENCRYPTION_INITIAL);
// Verify PTO is correctly set.
- int pto_rttvar_multiplier =
- GetQuicReloadableFlag(quic_default_on_pto) ? 2 : 4;
QuicTime::Delta expected_pto_delay =
- srtt + pto_rttvar_multiplier * rtt_stats->mean_deviation() +
+ srtt + GetPtoRttvarMultiplier() * rtt_stats->mean_deviation() +
QuicTime::Delta::Zero();
EXPECT_EQ(clock_.Now() + expected_pto_delay,
manager_.GetRetransmissionTime());
@@ -3335,14 +3332,14 @@
if (GetQuicReloadableFlag(quic_fix_arm_pto_for_application_data)) {
expected_pto_delay =
- srtt + pto_rttvar_multiplier * rtt_stats->mean_deviation();
+ srtt + GetPtoRttvarMultiplier() * rtt_stats->mean_deviation();
// Verify PTO timeout is now based on packet 7.
EXPECT_EQ(packet7_sent_time + expected_pto_delay * 2,
manager_.GetRetransmissionTime());
} else {
expected_pto_delay =
- srtt + pto_rttvar_multiplier * rtt_stats->mean_deviation() +
+ srtt + GetPtoRttvarMultiplier() * rtt_stats->mean_deviation() +
QuicTime::Delta::FromMilliseconds(kDefaultDelayedAckTimeMs);
// Verify PTO timeout is now based on packet 6.
EXPECT_EQ(packet6_sent_time + expected_pto_delay * 2,
@@ -3354,7 +3351,7 @@
// Forward progress has been made, verify PTO counter gets reset. PTO timeout
// is armed by left edge.
expected_pto_delay =
- srtt + pto_rttvar_multiplier * rtt_stats->mean_deviation() +
+ srtt + GetPtoRttvarMultiplier() * rtt_stats->mean_deviation() +
QuicTime::Delta::FromMilliseconds(kDefaultDelayedAckTimeMs);
EXPECT_EQ(packet4_sent_time + expected_pto_delay,
manager_.GetRetransmissionTime());
@@ -3376,10 +3373,8 @@
SendDataPacket(1, ENCRYPTION_INITIAL);
const QuicTime packet1_sent_time = clock_.Now();
// Verify PTO is correctly set.
- int pto_rttvar_multiplier =
- GetQuicReloadableFlag(quic_default_on_pto) ? 2 : 4;
QuicTime::Delta expected_pto_delay =
- srtt + pto_rttvar_multiplier * rtt_stats->mean_deviation() +
+ srtt + GetPtoRttvarMultiplier() * rtt_stats->mean_deviation() +
QuicTime::Delta::Zero();
EXPECT_EQ(packet1_sent_time + expected_pto_delay,
manager_.GetRetransmissionTime());
@@ -3414,7 +3409,7 @@
// Discard handshake keys.
manager_.SetHandshakeConfirmed();
expected_pto_delay =
- srtt + pto_rttvar_multiplier * rtt_stats->mean_deviation() +
+ srtt + GetPtoRttvarMultiplier() * rtt_stats->mean_deviation() +
QuicTime::Delta::FromMilliseconds(kDefaultDelayedAckTimeMs);
// Verify PTO timeout is now based on packet 3 as handshake is
// complete/confirmed.
@@ -3446,10 +3441,8 @@
SendDataPacket(1, ENCRYPTION_FORWARD_SECURE);
// Verify PTO is correctly set.
- int pto_rttvar_multiplier =
- GetQuicReloadableFlag(quic_default_on_pto) ? 2 : 4;
QuicTime::Delta expected_pto_delay =
- srtt + pto_rttvar_multiplier * rtt_stats->mean_deviation() +
+ srtt + GetPtoRttvarMultiplier() * rtt_stats->mean_deviation() +
QuicTime::Delta::FromMilliseconds(kDefaultDelayedAckTimeMs);
const QuicTime packet1_sent_time = clock_.Now();
EXPECT_EQ(packet1_sent_time + expected_pto_delay,
@@ -3489,7 +3482,7 @@
ENCRYPTION_FORWARD_SECURE));
expected_pto_delay =
rtt_stats->SmoothedOrInitialRtt() +
- std::max(pto_rttvar_multiplier * rtt_stats->mean_deviation(),
+ std::max(GetPtoRttvarMultiplier() * rtt_stats->mean_deviation(),
QuicTime::Delta::FromMilliseconds(1)) +
QuicTime::Delta::FromMilliseconds(kDefaultDelayedAckTimeMs);
@@ -3522,10 +3515,8 @@
SendDataPacket(1, ENCRYPTION_FORWARD_SECURE);
// Verify PTO is correctly set.
- int pto_rttvar_multiplier =
- GetQuicReloadableFlag(quic_default_on_pto) ? 2 : 4;
QuicTime::Delta expected_pto_delay =
- srtt + pto_rttvar_multiplier * rtt_stats->mean_deviation() +
+ srtt + GetPtoRttvarMultiplier() * rtt_stats->mean_deviation() +
QuicTime::Delta::FromMilliseconds(kDefaultDelayedAckTimeMs);
const QuicTime packet1_sent_time = clock_.Now();
EXPECT_EQ(packet1_sent_time + expected_pto_delay,
@@ -3555,7 +3546,7 @@
// Verify PTO period gets set to twice the expected value and based on
// packet3 (right edge).
expected_pto_delay =
- srtt + pto_rttvar_multiplier * rtt_stats->mean_deviation() +
+ srtt + GetPtoRttvarMultiplier() * rtt_stats->mean_deviation() +
QuicTime::Delta::FromMilliseconds(kDefaultDelayedAckTimeMs);
QuicTime packet3_sent_time = clock_.Now();
EXPECT_EQ(packet3_sent_time + expected_pto_delay * 2,
@@ -3572,7 +3563,7 @@
ENCRYPTION_FORWARD_SECURE));
expected_pto_delay =
rtt_stats->SmoothedOrInitialRtt() +
- std::max(pto_rttvar_multiplier * rtt_stats->mean_deviation(),
+ std::max(GetPtoRttvarMultiplier() * rtt_stats->mean_deviation(),
QuicTime::Delta::FromMilliseconds(1)) +
QuicTime::Delta::FromMilliseconds(kDefaultDelayedAckTimeMs);
@@ -3612,10 +3603,9 @@
SendDataPacket(1, ENCRYPTION_FORWARD_SECURE);
// Verify PTO is correctly set using standard deviation.
- int pto_rttvar_multiplier =
- GetQuicReloadableFlag(quic_default_on_pto) ? 2 : 4;
QuicTime::Delta expected_pto_delay =
- srtt + pto_rttvar_multiplier * rtt_stats->GetStandardOrMeanDeviation() +
+ srtt +
+ GetPtoRttvarMultiplier() * rtt_stats->GetStandardOrMeanDeviation() +
QuicTime::Delta::FromMilliseconds(kDefaultDelayedAckTimeMs);
EXPECT_EQ(clock_.Now() + expected_pto_delay,
manager_.GetRetransmissionTime());
@@ -3649,10 +3639,8 @@
SendDataPacket(1, ENCRYPTION_INITIAL);
const QuicTime packet1_sent_time = clock_.Now();
// Verify PTO is correctly set.
- int pto_rttvar_multiplier =
- GetQuicReloadableFlag(quic_default_on_pto) ? 2 : 4;
QuicTime::Delta expected_pto_delay =
- srtt + pto_rttvar_multiplier * rtt_stats->mean_deviation() +
+ srtt + GetPtoRttvarMultiplier() * rtt_stats->mean_deviation() +
QuicTime::Delta::Zero();
EXPECT_EQ(packet1_sent_time + expected_pto_delay,
manager_.GetRetransmissionTime());
@@ -3689,7 +3677,7 @@
// Verify PTO timeout is now based on packet 3 as handshake is
// complete/confirmed.
expected_pto_delay =
- srtt + pto_rttvar_multiplier * rtt_stats->mean_deviation() +
+ srtt + GetPtoRttvarMultiplier() * rtt_stats->mean_deviation() +
QuicTime::Delta::FromMilliseconds(kDefaultDelayedAckTimeMs);
EXPECT_EQ(packet3_sent_time + expected_pto_delay,
manager_.GetRetransmissionTime());
@@ -3729,10 +3717,8 @@
SendDataPacket(1, ENCRYPTION_INITIAL);
const QuicTime packet1_sent_time = clock_.Now();
// Verify PTO is correctly set.
- int pto_rttvar_multiplier =
- GetQuicReloadableFlag(quic_default_on_pto) ? 2 : 4;
QuicTime::Delta expected_pto_delay =
- srtt + pto_rttvar_multiplier * rtt_stats->mean_deviation() +
+ srtt + GetPtoRttvarMultiplier() * rtt_stats->mean_deviation() +
QuicTime::Delta::Zero();
EXPECT_EQ(packet1_sent_time + expected_pto_delay,
manager_.GetRetransmissionTime());
@@ -3769,7 +3755,7 @@
// Verify PTO timeout is now based on packet 3 as handshake is
// complete/confirmed.
expected_pto_delay =
- srtt + pto_rttvar_multiplier * rtt_stats->mean_deviation() +
+ srtt + GetPtoRttvarMultiplier() * rtt_stats->mean_deviation() +
QuicTime::Delta::FromMilliseconds(kDefaultDelayedAckTimeMs);
EXPECT_EQ(packet3_sent_time + expected_pto_delay,
manager_.GetRetransmissionTime());
@@ -3999,11 +3985,9 @@
manager_.OnAckFrameEnd(clock_.Now(), QuicPacketNumber(1),
ENCRYPTION_INITIAL));
RttStats* rtt_stats = const_cast<RttStats*>(manager_.GetRttStats());
- int pto_rttvar_multiplier =
- GetQuicReloadableFlag(quic_default_on_pto) ? 2 : 4;
const QuicTime::Delta pto_delay =
rtt_stats->smoothed_rtt() +
- pto_rttvar_multiplier * rtt_stats->mean_deviation() +
+ GetPtoRttvarMultiplier() * rtt_stats->mean_deviation() +
QuicTime::Delta::Zero();
// Verify PTO is armed based on handshake data.
EXPECT_EQ(packet2_sent_time + pto_delay, manager_.GetRetransmissionTime());
@@ -4074,10 +4058,8 @@
QuicTime packet2_sent_time = clock_.Now();
SendDataPacket(3, ENCRYPTION_HANDSHAKE);
// Verify PTO is correctly set based on packet 1.
- int pto_rttvar_multiplier =
- GetQuicReloadableFlag(quic_default_on_pto) ? 2 : 4;
QuicTime::Delta expected_pto_delay =
- srtt + pto_rttvar_multiplier * rtt_stats->mean_deviation() +
+ srtt + GetPtoRttvarMultiplier() * rtt_stats->mean_deviation() +
QuicTime::Delta::Zero();
EXPECT_EQ(packet1_sent_time + expected_pto_delay,
manager_.GetRetransmissionTime());
@@ -4196,10 +4178,8 @@
manager_.MaybeSendProbePackets();
// Verify PTO period gets set correctly.
- int pto_rttvar_multiplier =
- GetQuicReloadableFlag(quic_default_on_pto) ? 2 : 4;
expected_pto_delay =
- srtt + pto_rttvar_multiplier * rtt_stats->mean_deviation() +
+ srtt + GetPtoRttvarMultiplier() * rtt_stats->mean_deviation() +
QuicTime::Delta::FromMilliseconds(kDefaultDelayedAckTimeMs);
QuicTime sent_time = clock_.Now();
EXPECT_EQ(sent_time + expected_pto_delay * 2,
