// Copyright 2014 The Chromium Authors. All rights reserved. // Use of this source code is governed by a BSD-style license that can be // found in the LICENSE file. // This file intentionally does not have header guards, it's included // inside a macro to generate values. The following line silences a // presubmit warning that would otherwise be triggered by this: // no-include-guard-because-multiply-included // This file contains the list of QUIC protocol flags. // Time period for which a given connection_id should live in the time-wait // state. QUIC_FLAG(int64_t, FLAGS_quic_time_wait_list_seconds, 200) // Currently, this number is quite conservative. The max QPS limit for an // individual server silo is currently set to 1000 qps, though the actual max // that we see in the wild is closer to 450 qps. Regardless, this means that // the longest time-wait list we should see is 200 seconds * 1000 qps, 200000. // Of course, there are usually many queries per QUIC connection, so we allow a // factor of 3 leeway. // // Maximum number of connections on the time-wait list. A negative value implies // no configured limit. QUIC_FLAG(int64_t, FLAGS_quic_time_wait_list_max_connections, 600000) // Enables server-side support for QUIC stateless rejects. QUIC_FLAG(bool, FLAGS_quic_reloadable_flag_enable_quic_stateless_reject_support, true) // If true, require handshake confirmation for QUIC connections, functionally // disabling 0-rtt handshakes. // TODO(rtenneti): Enable this flag after CryptoServerTest's are fixed. QUIC_FLAG(bool, FLAGS_quic_reloadable_flag_quic_require_handshake_confirmation, false) // If true, disable pacing in QUIC. QUIC_FLAG(bool, FLAGS_quic_disable_pacing_for_perf_tests, false) // If true, QUIC will use cheap stateless rejects without creating a full // connection. QUIC_FLAG(bool, FLAGS_quic_reloadable_flag_quic_use_cheap_stateless_rejects, true) // If true, allows packets to be buffered in anticipation of a future CHLO, and // allow CHLO packets to be buffered until next iteration of the event loop. QUIC_FLAG(bool, FLAGS_quic_allow_chlo_buffering, true) // If greater than zero, mean RTT variation is multiplied by the specified // factor and added to the congestion window limit. QUIC_FLAG(double, FLAGS_quic_bbr_rtt_variation_weight, 0.0f) // Congestion window gain for QUIC BBR during PROBE_BW phase. QUIC_FLAG(double, FLAGS_quic_bbr_cwnd_gain, 2.0f) // Simplify QUIC\'s adaptive time loss detection to measure the necessary // reordering window for every spurious retransmit. QUIC_FLAG(bool, FLAGS_quic_reloadable_flag_quic_fix_adaptive_time_loss, false) // Allows the 3RTO QUIC connection option to close a QUIC connection after // 3RTOs if there are no open streams. QUIC_FLAG(bool, FLAGS_quic_reloadable_flag_quic_enable_3rtos, false) // When true, defaults to BBR congestion control instead of Cubic. QUIC_FLAG(bool, FLAGS_quic_reloadable_flag_quic_default_to_bbr, false) // If buffered data in QUIC stream is less than this threshold, buffers all // provided data or asks upper layer for more data. QUIC_FLAG(uint32_t, FLAGS_quic_buffered_data_threshold, 8192u) // Max size of data slice in bytes for QUIC stream send buffer. QUIC_FLAG(uint32_t, FLAGS_quic_send_buffer_max_data_slice_size, 4096u) // If true, QUIC supports both QUIC Crypto and TLS 1.3 for the handshake // protocol. QUIC_FLAG(bool, FLAGS_quic_supports_tls_handshake, false) // Allow QUIC to accept initial packet numbers that are random, not 1. QUIC_FLAG(bool, FLAGS_quic_restart_flag_quic_enable_accept_random_ipn, false) // If true, enable QUIC v43. QUIC_FLAG(bool, FLAGS_quic_reloadable_flag_quic_enable_version_43, true) // Enables 3 new connection options to make PROBE_RTT more aggressive QUIC_FLAG(bool, FLAGS_quic_reloadable_flag_quic_bbr_less_probe_rtt, false) // If true, limit quic stream length to be below 2^62. QUIC_FLAG(bool, FLAGS_quic_reloadable_flag_quic_stream_too_long, true) // If true, enable QUIC v99. QUIC_FLAG(bool, FLAGS_quic_enable_version_99, false) QUIC_FLAG(bool, FLAGS_quic_reloadable_flag_quic_disable_version_41_2, true) // When true, set the initial congestion control window from connection options // in QuicSentPacketManager rather than TcpCubicSenderBytes. QUIC_FLAG(bool, FLAGS_quic_reloadable_flag_quic_unified_iw_options, false) // Number of packets that the pacing sender allows in bursts during pacing. QUIC_FLAG(int32_t, FLAGS_quic_lumpy_pacing_size, 1) // Congestion window fraction that the pacing sender allows in bursts during // pacing. QUIC_FLAG(double, FLAGS_quic_lumpy_pacing_cwnd_fraction, 0.25f) // Default enables QUIC ack decimation and adds a connection option to disable // it. QUIC_FLAG(bool, FLAGS_quic_reloadable_flag_quic_enable_ack_decimation, false) // If true, QUIC offload pacing when using USPS as egress method. QUIC_FLAG(bool, FLAGS_quic_restart_flag_quic_offload_pacing_to_usps2, false) // Max time that QUIC can pace packets into the future in ms. QUIC_FLAG(int32_t, FLAGS_quic_max_pace_time_into_future_ms, 10) // Smoothed RTT fraction that a connection can pace packets into the future. QUIC_FLAG(double, FLAGS_quic_pace_time_into_future_srtt_fraction, 0.125f) // If true, enable QUIC v44. QUIC_FLAG(bool, FLAGS_quic_reloadable_flag_quic_enable_version_44, true) // If true, QuicConnection::ProcessPacket will add the connection to write // blocked list if it is write blocked, and will not attempt to write before the // writer unblocks. QUIC_FLAG(bool, FLAGS_quic_reloadable_flag_quic_add_to_blocked_list_if_writer_blocked, true) // Only send an ack immediately when a previously missing packet is received if // an ack with a larger largest acked has already been sent. QUIC_FLAG(bool, FLAGS_quic_reloadable_flag_quic_ack_reordered_packets, true) // If true, QuicWriteBlockedList will use StaticStreamCollection to speed up // operations on static streams. QUIC_FLAG( bool, FLAGS_quic_reloadable_flag_quic_use_static_stream_collection_in_write_blocked_list, true) // If true, disables QUIC v42. QUIC_FLAG(bool, FLAGS_quic_reloadable_flag_quic_disable_version_42, true) // Stop checking QuicUnackedPacketMap::HasUnackedRetransmittableFrames and // instead rely on the existing check that bytes_in_flight > 0 QUIC_FLAG(bool, FLAGS_quic_reloadable_flag_quic_optimize_inflight_check, false) // When you\'re app-limited entering recovery, stay app-limited until you exit // recovery in QUIC BBR. QUIC_FLAG(bool, FLAGS_quic_reloadable_flag_quic_bbr_app_limited_recovery, true) // If true, mark QUIC as app-limited after sending queued packets or // retransmisssions and we then become congestion control blocked. QUIC_FLAG(bool, FLAGS_quic_reloadable_flag_quic_retransmissions_app_limited, true) // If true, stop resetting ideal_next_packet_send_time_ in pacing sender. QUIC_FLAG( bool, FLAGS_quic_reloadable_flag_quic_donot_reset_ideal_next_packet_send_time, false) // If true, enable experiment for testing PCC congestion-control. QUIC_FLAG(bool, FLAGS_quic_reloadable_flag_quic_enable_pcc3, false) // If true, fix potential crashes in QuicSession::RetransmitLostData. QUIC_FLAG(bool, FLAGS_quic_reloadable_flag_quic_fix_retransmit_lost_data, true) // When true, ensure BBR allows at least one MSS to be sent in response to an // ACK in packet conservation. QUIC_FLAG(bool, FLAGS_quic_reloadable_flag_quic_bbr_one_mss_conservation, false) // Add 3 connection options to decrease the pacing and CWND gain in QUIC BBR // STARTUP. QUIC_FLAG(bool, FLAGS_quic_reloadable_flag_quic_bbr_slower_startup3, false) // When true, the LOSS connection option allows for 1/8 RTT of reording instead // of the current 1/8th threshold which has been found to be too large for fast // loss recovery. QUIC_FLAG(bool, FLAGS_quic_reloadable_flag_quic_eighth_rtt_loss_detection, false) // Enables the BBQ5 connection option, which forces saved aggregation values to // expire when the bandwidth increases more than 25% in QUIC BBR STARTUP. QUIC_FLAG(bool, FLAGS_quic_reloadable_flag_quic_bbr_slower_startup4, false) // If true, QuicCryptoServerConfig::EvaluateClientHello will use GetCertChain // instead of the more expensive GetProof. QUIC_FLAG(bool, FLAGS_quic_reloadable_flag_quic_use_get_cert_chain, false)