Add upper bound flag FLAGS_quic_time_wait_list_max_pending_packets (default to 1K) for pending_queued_packets_ in time wait list.
Protected by FLAGS_quic_reloadable_flag_quic_add_upperbound_for_queued_packets.
PiperOrigin-RevId: 391175110
diff --git a/quic/core/quic_flags_list.h b/quic/core/quic_flags_list.h
index 1af71b6..0eedd30 100644
--- a/quic/core/quic_flags_list.h
+++ b/quic/core/quic_flags_list.h
@@ -97,6 +97,8 @@
QUIC_FLAG(FLAGS_quic_reloadable_flag_quic_require_handshake_confirmation, false)
// If true, reset per packet state before processing undecryptable packets.
QUIC_FLAG(FLAGS_quic_reloadable_flag_quic_reset_per_packet_state_for_undecryptable_packets, true)
+// If true, respect FLAGS_quic_time_wait_list_max_pending_packets as the upper bound of queued packets in time wait list.
+QUIC_FLAG(FLAGS_quic_reloadable_flag_quic_add_upperbound_for_queued_packets, true)
// If true, send PATH_RESPONSE upon receiving PATH_CHALLENGE regardless of perspective. --gfe2_reloadable_flag_quic_start_peer_migration_earlier has to be true before turn on this flag.
QUIC_FLAG(FLAGS_quic_reloadable_flag_quic_send_path_response2, true)
// If true, set burst token to 2 in cwnd bootstrapping experiment.
diff --git a/quic/core/quic_protocol_flags_list.h b/quic/core/quic_protocol_flags_list.h
index 56f8359..62c1712 100644
--- a/quic/core/quic_protocol_flags_list.h
+++ b/quic/core/quic_protocol_flags_list.h
@@ -44,6 +44,12 @@
"Time period for which a given connection_id should live in "
"the time-wait state.")
+// This number is relatively conservative. For example, there are at most 1K
+// queued stateless resets, which consume 1K * 21B = 21KB.
+QUIC_PROTOCOL_FLAG(
+ uint64_t, quic_time_wait_list_max_pending_packets, 1024,
+ "Upper limit of pending packets in time wait list when writer is blocked.")
+
QUIC_PROTOCOL_FLAG(double,
quic_bbr_cwnd_gain,
2.0f,
diff --git a/quic/core/quic_time_wait_list_manager.cc b/quic/core/quic_time_wait_list_manager.cc
index 12f5ef9..69b85fa 100644
--- a/quic/core/quic_time_wait_list_manager.cc
+++ b/quic/core/quic_time_wait_list_manager.cc
@@ -392,6 +392,13 @@
QUIC_LOG(ERROR) << "Tried to send or queue a null packet";
return true;
}
+ if (GetQuicReloadableFlag(quic_add_upperbound_for_queued_packets) &&
+ pending_packets_queue_.size() >=
+ GetQuicFlag(FLAGS_quic_time_wait_list_max_pending_packets)) {
+ // There are too many pending packets.
+ QUIC_CODE_COUNT(quic_too_many_pending_packets_in_time_wait);
+ return true;
+ }
if (WriteToWire(packet.get())) {
// Allow the packet to be deleted upon leaving this function.
return true;
diff --git a/quic/core/quic_time_wait_list_manager_test.cc b/quic/core/quic_time_wait_list_manager_test.cc
index f47bdf2..49e8b27 100644
--- a/quic/core/quic_time_wait_list_manager_test.cc
+++ b/quic/core/quic_time_wait_list_manager_test.cc
@@ -768,6 +768,37 @@
nullptr, nullptr);
}
+TEST_F(QuicTimeWaitListManagerTest, TooManyPendingPackets) {
+ SetQuicFlag(FLAGS_quic_time_wait_list_max_pending_packets, 5);
+ const size_t kNumOfUnProcessablePackets = 2048;
+ EXPECT_CALL(visitor_, OnWriteBlocked(&time_wait_list_manager_))
+ .Times(testing::AnyNumber());
+ // Write block for the next packets.
+ EXPECT_CALL(writer_,
+ WritePacket(_, _, self_address_.host(), peer_address_, _))
+ .With(Args<0, 1>(PublicResetPacketEq(TestConnectionId(1))))
+ .WillOnce(DoAll(Assign(&writer_is_blocked_, true),
+ Return(WriteResult(WRITE_STATUS_BLOCKED, EAGAIN))));
+ for (size_t i = 0; i < kNumOfUnProcessablePackets; ++i) {
+ time_wait_list_manager_.SendPublicReset(
+ self_address_, peer_address_, TestConnectionId(1),
+ /*ietf_quic=*/true,
+ /*received_packet_length=*/
+ QuicFramer::GetMinStatelessResetPacketLength() + 1,
+ /*packet_context=*/nullptr);
+ }
+ if (GetQuicReloadableFlag(quic_add_upperbound_for_queued_packets)) {
+ // Verify pending packet queue size is limited.
+ EXPECT_EQ(5u, QuicTimeWaitListManagerPeer::PendingPacketsQueueSize(
+ &time_wait_list_manager_));
+ } else {
+ // The pending packet queue grows unbounded.
+ EXPECT_EQ(kNumOfUnProcessablePackets,
+ QuicTimeWaitListManagerPeer::PendingPacketsQueueSize(
+ &time_wait_list_manager_));
+ }
+}
+
} // namespace
} // namespace test
} // namespace quic
diff --git a/quic/test_tools/quic_time_wait_list_manager_peer.cc b/quic/test_tools/quic_time_wait_list_manager_peer.cc
index 8f614e8..cbcd36e 100644
--- a/quic/test_tools/quic_time_wait_list_manager_peer.cc
+++ b/quic/test_tools/quic_time_wait_list_manager_peer.cc
@@ -36,5 +36,11 @@
return manager->SendOrQueuePacket(std::move(packet), packet_context);
}
+// static
+size_t QuicTimeWaitListManagerPeer::PendingPacketsQueueSize(
+ QuicTimeWaitListManager* manager) {
+ return manager->pending_packets_queue_.size();
+}
+
} // namespace test
} // namespace quic
diff --git a/quic/test_tools/quic_time_wait_list_manager_peer.h b/quic/test_tools/quic_time_wait_list_manager_peer.h
index 4e0a4a7..a314e03 100644
--- a/quic/test_tools/quic_time_wait_list_manager_peer.h
+++ b/quic/test_tools/quic_time_wait_list_manager_peer.h
@@ -26,6 +26,8 @@
QuicTimeWaitListManager* manager,
std::unique_ptr<QuicTimeWaitListManager::QueuedPacket> packet,
const QuicPerPacketContext* packet_context);
+
+ static size_t PendingPacketsQueueSize(QuicTimeWaitListManager* manager);
};
} // namespace test
