quiche/recovery/congestion/bbr2/
pacing.rs

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26
27use self::rtt::INITIAL_RTT;
28
29use super::*;
30
31// BBR2 Transmit Packet Pacing Functions
32//
33
34// 4.6.2.  Pacing Rate: BBR.pacing_rate
35pub fn bbr2_init_pacing_rate(r: &mut Congestion) {
36    let bbr = &mut r.bbr2_state;
37
38    let srtt = INITIAL_RTT.as_secs_f64();
39
40    // At init, cwnd is initcwnd.
41    let nominal_bandwidth = r.congestion_window as f64 / srtt;
42
43    bbr.pacing_rate = (STARTUP_PACING_GAIN * nominal_bandwidth) as u64;
44    bbr.init_pacing_rate = (STARTUP_PACING_GAIN * nominal_bandwidth) as u64;
45}
46
47pub fn bbr2_set_pacing_rate_with_gain(r: &mut Congestion, pacing_gain: f64) {
48    let rate = (pacing_gain *
49        r.bbr2_state.bw as f64 *
50        (1.0 - PACING_MARGIN_PERCENT)) as u64;
51
52    if r.bbr2_state.filled_pipe ||
53        rate > r.bbr2_state.pacing_rate ||
54        r.bbr2_state.pacing_rate == r.bbr2_state.init_pacing_rate
55    {
56        r.bbr2_state.pacing_rate = rate;
57    }
58}
59
60pub fn bbr2_set_pacing_rate(r: &mut Congestion) {
61    bbr2_set_pacing_rate_with_gain(r, r.bbr2_state.pacing_gain);
62}
quiche/recovery/congestion/bbr2/pacing.rs

quiche/recovery/congestion/bbr2/
pacing.rs
