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//! Registry drive loop — poll, tick, and fanout.
//!
//! Split from `registry/mod.rs` to keep the struct/insert/routing concern
//! separate from the per-iteration state machine driving concern.
use std::time::Instant;
use crate::fanout::fanout;
use crate::ids::SfuRid;
use crate::propagate::{ClientId, Propagated};
use super::Registry;
impl Registry {
/// Poll every client until each returns a `Timeout`, queuing propagated events.
///
/// Returns the earliest next wake-up deadline.
pub fn poll_all(&mut self, now: Instant) -> Instant {
let mut deadline = now + std::time::Duration::from_millis(100);
for client in self.clients.iter_mut() {
loop {
if !client.is_alive() {
break;
}
match client.poll_output() {
Propagated::Timeout(t) => {
deadline = deadline.min(t);
break;
}
Propagated::Noop => continue,
Propagated::BandwidthEstimate {
peer_id,
ref estimate,
} => {
self.metrics.update_peer_bwe(*peer_id, estimate.bps);
self.to_propagate.push_back(Propagated::BandwidthEstimate {
peer_id,
estimate: *estimate,
});
#[cfg(feature = "pacer")]
{
use crate::bwe::PacerAction;
match client.drive_pacer(estimate.bps) {
PacerAction::GoAudioOnly => {
self.to_propagate.push_back(Propagated::AudioOnlyMode {
peer_id,
audio_only: true,
});
}
PacerAction::RestoreVideo => {
self.to_propagate.push_back(Propagated::AudioOnlyMode {
peer_id,
audio_only: false,
});
}
PacerAction::SuspendVideo => {
client.set_suspended(true);
self.metrics.inc_suspend_video("enter");
self.to_propagate.push_back(Propagated::SuspendVideo {
peer_id,
suspended: true,
});
}
PacerAction::RestoreAudio => {
client.set_suspended(false);
self.metrics.inc_suspend_video("exit");
self.to_propagate.push_back(Propagated::SuspendVideo {
peer_id,
suspended: false,
});
}
PacerAction::ChangeLayer(_) | PacerAction::NoChange => {}
}
}
}
Propagated::RtcpStats { peer_id, ref stats } => {
self.metrics.update_peer_rtcp(
*peer_id,
stats.fraction_lost,
stats.rtt.as_secs_f64() * 1000.0,
stats.jitter.as_secs_f64() * 1000.0,
);
self.to_propagate.push_back(Propagated::RtcpStats {
peer_id,
stats: *stats,
});
}
other => {
#[cfg(feature = "active-speaker")]
if let Propagated::MediaData(ref origin, ref data) = other {
// RFC 6464: str0m stores audio_level as negated dBov
// (0 = loudest, -127 = silent). The detector expects
// 0-127 dBov (0 = loud, 127 = silent), so we negate.
// MediaData originates from the current loop \, so
// we check client.is_relay() directly — no second borrow needed.
if let Some(raw) = data.audio_level_raw() {
if !client.is_relay() {
let level = (-(raw as i16)).clamp(0, 127) as u8;
let now_ms = self.detector_epoch.elapsed().as_millis() as u64;
self.detector.record_level(**origin, level, now_ms);
}
}
}
self.to_propagate.push_back(other);
}
}
}
}
deadline
}
/// Advance the dominant-speaker detector one tick.
///
/// Queues a [`Propagated::ActiveSpeakerChanged`] when dominance changes.
/// Call this on a 300ms interval (see `dominant_speaker::TICK_INTERVAL`).
/// Only available with the `active-speaker` feature.
#[cfg(feature = "active-speaker")]
#[cfg_attr(docsrs, doc(cfg(feature = "active-speaker")))]
pub fn tick_active_speaker(&mut self, now: Instant) {
let now_ms = now
.saturating_duration_since(self.detector_epoch)
.as_millis() as u64;
if let Some(change) = self.detector.tick(now_ms) {
self.metrics.inc_dominant_speaker_changes();
self.to_propagate
.push_back(Propagated::ActiveSpeakerChanged {
peer_id: change.peer_id,
confidence: change.c2_margin,
});
}
}
/// Update Prometheus gauges with current per-peer speaker activity scores.
///
/// Call this periodically (e.g. on the same 300ms tick as `tick_active_speaker`).
/// Only available with both `active-speaker` and `metrics-prometheus` features.
#[cfg(all(feature = "active-speaker", feature = "metrics-prometheus"))]
#[cfg_attr(
docsrs,
doc(cfg(all(feature = "active-speaker", feature = "metrics-prometheus")))
)]
pub fn tick_speaker_scores(&mut self) {
for (peer_id, imm, med, lng) in self.detector.peer_scores() {
self.metrics
.update_peer_speaker_scores(peer_id, imm, med, lng);
}
}
/// Drive the session clock forward on every client.
pub fn tick(&mut self, now: Instant) {
for client in self.clients.iter_mut() {
client.handle_timeout(now);
}
}
/// Fan out every queued propagated event to the appropriate clients.
pub fn fanout_pending(&mut self) {
#[cfg(feature = "kalman-bwe")]
let now = Instant::now();
while let Some(p) = self.to_propagate.pop_front() {
#[cfg(feature = "kalman-bwe")]
if let Propagated::ClientBudgetHint(subscriber_id, bps) = &p {
self.bandwidth.record_client_hint(*subscriber_id, *bps, now);
continue;
}
// Update pacer-driven layer selection before forwarding the packet
// so subscribers receive media on their freshly-chosen layer.
#[cfg(all(feature = "kalman-bwe", feature = "pacer"))]
if let Propagated::MediaData(origin, _) = &p {
self.update_pacer_layers(*origin);
}
fanout(&p, &mut self.clients);
}
}
/// Compute the maximum desired simulcast layer across all subscribers per publisher,
/// and enqueue [`Propagated::PublisherLayerHint`] when the max changes.
///
/// Call after [`fanout_pending`][Self::fanout_pending] on any tick where
/// subscriber desired layers may have changed.
pub fn emit_publisher_layer_hints(&mut self) {
use crate::client::layer;
use std::collections::HashMap;
let mut max_per_publisher: HashMap<ClientId, SfuRid> = HashMap::new();
for subscriber in &self.clients {
let sub_desired = subscriber.desired_layer();
for track_out in &subscriber.tracks_out {
if let Some(track_in) = track_out.track_in.upgrade() {
let publisher_id = track_in.origin;
let entry = max_per_publisher.entry(publisher_id).or_insert(layer::LOW);
let rank = |r: SfuRid| -> u8 {
if r == SfuRid::LOW {
0
} else if r == SfuRid::MEDIUM {
1
} else {
2
}
};
if rank(sub_desired) > rank(*entry) {
*entry = sub_desired;
}
}
}
}
for (publisher_id, max_rid) in max_per_publisher {
let is_relay = self
.clients
.iter()
.any(|c| c.id == publisher_id && c.is_relay());
if is_relay {
self.to_propagate
.push_back(Propagated::PublisherLayerHintForUpstream {
publisher_relay_id: publisher_id,
max_rid,
});
} else {
self.to_propagate.push_back(Propagated::PublisherLayerHint {
publisher_id,
max_rid,
});
}
}
}
}
/// Default simulcast ladder used when the publisher has not yet emitted active RIDs.
#[cfg(all(feature = "kalman-bwe", feature = "pacer"))]
const DEFAULT_SIMULCAST_LADDER: &[crate::ids::SfuRid] = &[
crate::ids::SfuRid::LOW,
crate::ids::SfuRid::MEDIUM,
crate::ids::SfuRid::HIGH,
];
#[cfg(all(feature = "kalman-bwe", feature = "pacer"))]
impl Registry {
/// For every subscriber of `origin`, read the current Kalman BWE estimate
/// and advance the subscriber's pacer to select the appropriate simulcast layer.
///
/// Called on every incoming `MediaData` event from the publisher so the
/// pacer has fresh input every 20ms (nominal video packet cadence).
///
/// Only available with both `kalman-bwe` and `pacer` features.
pub fn update_pacer_layers(&mut self, origin: crate::propagate::ClientId) {
let now = std::time::Instant::now();
// Snapshot publisher's active RIDs before the mutable loop (borrow checker).
let publisher_rids: Vec<crate::ids::SfuRid> = self
.clients
.iter()
.find(|c| c.id == origin)
.map(|c| c.active_rids())
.unwrap_or_default();
let _available: &[crate::ids::SfuRid] = if publisher_rids.is_empty() {
DEFAULT_SIMULCAST_LADDER
} else {
&publisher_rids
};
let subscriber_ids: Vec<crate::propagate::ClientId> = self
.clients
.iter()
.filter(|c| c.id != origin)
.map(|c| c.id)
.collect();
for sub_id in subscriber_ids {
let budget = self.bandwidth.estimate_bps(sub_id, now).unwrap_or(0);
// Mirror update_peer_bwe so Prometheus stays in sync.
#[cfg(feature = "metrics-prometheus")]
self.metrics.update_peer_bwe(*sub_id, budget);
if let Some(client) = self.clients.iter_mut().find(|c| c.id == sub_id) {
use crate::bwe::PacerAction;
match client.drive_pacer(budget) {
PacerAction::GoAudioOnly => {
self.to_propagate.push_back(Propagated::AudioOnlyMode {
peer_id: sub_id,
audio_only: true,
});
}
PacerAction::RestoreVideo => {
self.to_propagate.push_back(Propagated::AudioOnlyMode {
peer_id: sub_id,
audio_only: false,
});
}
PacerAction::SuspendVideo => {
client.set_suspended(true);
self.metrics.inc_suspend_video("enter");
self.to_propagate.push_back(Propagated::SuspendVideo {
peer_id: sub_id,
suspended: true,
});
}
PacerAction::RestoreAudio => {
client.set_suspended(false);
self.metrics.inc_suspend_video("exit");
self.to_propagate.push_back(Propagated::SuspendVideo {
peer_id: sub_id,
suspended: false,
});
}
PacerAction::ChangeLayer(_) | PacerAction::NoChange => {}
}
}
}
}
}