quiche/recovery/congestion/bbr2/
init.rs

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26
27use super::*;
28
29use std::time::Instant;
30
31// BBR2 Functions at Initialization.
32//
33
34// 4.2.1.  Initialization
35pub fn bbr2_init(r: &mut Congestion) {
36    let now = Instant::now();
37
38    let bbr = &mut r.bbr2_state;
39    bbr.min_rtt = r.initial_rtt;
40    bbr.min_rtt_stamp = now;
41    bbr.probe_rtt_done_stamp = None;
42    bbr.probe_rtt_round_done = false;
43    bbr.prior_cwnd = 0;
44    bbr.idle_restart = false;
45    bbr.extra_acked_interval_start = now;
46    bbr.extra_acked_delivered = 0;
47    bbr.bw_lo = u64::MAX;
48    bbr.bw_hi = u64::MAX;
49    bbr.inflight_lo = usize::MAX;
50    bbr.inflight_hi = usize::MAX;
51    bbr.probe_up_cnt = usize::MAX;
52
53    r.send_quantum = r.max_datagram_size;
54
55    per_loss::bbr2_reset_congestion_signals(r);
56    per_loss::bbr2_reset_lower_bounds(r);
57    bbr2_init_round_counting(r);
58    bbr2_init_full_pipe(r);
59    pacing::bbr2_init_pacing_rate(r);
60    bbr2_enter_startup(r);
61}
62
63// 4.5.1.  BBR.round_count: Tracking Packet-Timed Round Trips
64fn bbr2_init_round_counting(r: &mut Congestion) {
65    let bbr = &mut r.bbr2_state;
66
67    bbr.next_round_delivered = 0;
68    bbr.round_start = false;
69    bbr.round_count = 0;
70}
71
72// 4.3.1.1.  Startup Dynamics
73pub fn bbr2_enter_startup(r: &mut Congestion) {
74    let bbr = &mut r.bbr2_state;
75
76    bbr.state = BBR2StateMachine::Startup;
77    bbr.pacing_gain = STARTUP_PACING_GAIN;
78    bbr.cwnd_gain = STARTUP_CWND_GAIN;
79}
80
81// 4.3.1.2.  Exiting Startup Based on Bandwidth Plateau
82fn bbr2_init_full_pipe(r: &mut Congestion) {
83    let bbr = &mut r.bbr2_state;
84
85    bbr.filled_pipe = false;
86    bbr.full_bw = 0;
87    bbr.full_bw_count = 0;
88}
quiche/recovery/congestion/bbr2/init.rs

quiche/recovery/congestion/bbr2/
init.rs
