rtcpThrottle -> pliThrottle

config-sample.yaml

@@ -36,6 +36,14 @@ rtc:
 #  # LiveKit will automatically configure connected clients to use the same STUN servers
 #  stun_servers:
 #    - server1
+#  # minimum amount of time between pli/fir rtcp packets being sent to an individual
+#  # producer. Increasing these times can lead to longer black screens when participants join,
+#  # while reducing them can lead to higher producer bitrates.
+#  pli_throttle:
+#    low_quality: 1s
+#    mid_quality: 2s
+#    high_quality: 3s
+
 
 # API key / secret pairs.
 # Keys are used for JWT authentication, server APIs would require a keypair in order to generate access tokens

pkg/config/config.go

@@ -39,11 +39,11 @@ type RTCConfig struct {
 	// Max bitrate for REMB
 	MaxBitrate uint64 `yaml:"max_bitrate"`
 
-	// Throttle periods for rtcp packets
-	Throttle RTCPThrottleConfig `yaml:"rtcp_throttle"`
+	// Throttle periods for pli/fir rtcp packets
+	PLIThrottle PLIThrottleConfig `yaml:"pli_throttle"`
 }
 
-type RTCPThrottleConfig struct {
+type PLIThrottleConfig struct {
 	LowQuality  time.Duration `yaml:"low_quality"`
 	MidQuality  time.Duration `yaml:"mid_quality"`
 	HighQuality time.Duration `yaml:"high_quality"`
@@ -93,7 +93,7 @@ func NewConfig(confString string) (*Config, error) {
 			},
 			MaxBitrate:       3 * 1024 * 1024, // 3 mbps
 			PacketBufferSize: 500,
-			Throttle: RTCPThrottleConfig{
+			PLIThrottle: PLIThrottleConfig{
 				LowQuality:  time.Second,
 				MidQuality:  time.Second * 2,
 				HighQuality: time.Second * 3,

pkg/rtc/participant.go

@@ -37,7 +37,7 @@ type ParticipantParams struct {
 	AudioConfig     config.AudioConfig
 	ProtocolVersion types.ProtocolVersion
 	Stats           *RoomStatsReporter
-	ThrottleConfig  config.RTCPThrottleConfig
+	ThrottleConfig  config.PLIThrottleConfig
 }
 
 type ParticipantImpl struct {
@@ -50,7 +50,7 @@ type ParticipantImpl struct {
 	state             atomic.Value // livekit.ParticipantInfo_State
 	updateAfterActive atomic.Value // bool
 	rtcpCh            chan []rtcp.Packet
-	rtcpThrottle      *rtcpThrottle
+	pliThrottle       *pliThrottle
 
 	// reliable and unreliable data channels
 	reliableDC *webrtc.DataChannel
@@ -91,7 +91,7 @@ func NewParticipant(params ParticipantParams) (*ParticipantImpl, error) {
 		params:           params,
 		id:               utils.NewGuid(utils.ParticipantPrefix),
 		rtcpCh:           make(chan []rtcp.Packet, 50),
-		rtcpThrottle:     newRtcpThrottle(params.ThrottleConfig),
+		pliThrottle:      newPLIThrottle(params.ThrottleConfig),
 		subscribedTracks: make(map[string][]types.SubscribedTrack),
 		publishedTracks:  make(map[string]types.PublishedTrack, 0),
 		pendingTracks:    make(map[string]*livekit.TrackInfo),
@@ -401,7 +401,7 @@ func (p *ParticipantImpl) Close() error {
 	if onClose != nil {
 		onClose(p)
 	}
-	p.rtcpThrottle.close()
+	p.pliThrottle.close()
 	p.publisher.Close()
 	p.subscriber.Close()
 	close(p.rtcpCh)
@@ -739,7 +739,7 @@ func (p *ParticipantImpl) onMediaTrack(track *webrtc.TrackRemote, rtpReceiver *w
 	}
 
 	ssrc := uint32(track.SSRC())
-	p.rtcpThrottle.addTrack(ssrc, track.RID())
+	p.pliThrottle.addTrack(ssrc, track.RID())
 	if p.twcc == nil {
 		p.twcc = twcc.NewTransportWideCCResponder(ssrc)
 		p.twcc.OnFeedback(func(pkt rtcp.RawPacket) {
@@ -840,7 +840,7 @@ func (p *ParticipantImpl) handleTrackPublished(track types.PublishedTrack) {
 			p.onTrackUpdated(p, track)
 		}
 		if mt, ok := track.(*MediaTrack); ok {
-			p.rtcpThrottle.removeTrack(uint32(mt.ssrc))
+			p.pliThrottle.removeTrack(uint32(mt.ssrc))
 		}
 		track.OnClose(nil)
 	})
@@ -958,7 +958,7 @@ func (p *ParticipantImpl) rtcpSendWorker() {
 				continue
 			}
 
-			p.rtcpThrottle.add(mediaSSRC, func() { write([]rtcp.Packet{pkt}) })
+			p.pliThrottle.add(mediaSSRC, func() { write([]rtcp.Packet{pkt}) })
 		}
 
 		if len(fwdPkts) > 0 {

pkg/rtc/participant_internal_test.go

@@ -173,7 +173,7 @@ func newParticipantForTest(identity string) *ParticipantImpl {
 		Config:          rtcConf,
 		Sink:            &routingfakes.FakeMessageSink{},
 		ProtocolVersion: 0,
-		ThrottleConfig:  conf.RTC.Throttle,
+		ThrottleConfig:  conf.RTC.PLIThrottle,
 	})
 	return p
 }

pkg/rtc/plithrottle.go

@@ -9,8 +9,8 @@ import (
 	"github.com/livekit/livekit-server/pkg/config"
 )
 
-type rtcpThrottle struct {
-	config    config.RTCPThrottleConfig
+type pliThrottle struct {
+	config    config.PLIThrottleConfig
 	mu        sync.RWMutex
 	throttles map[uint32]func(func())
 }
@@ -22,14 +22,14 @@ const (
 	quarterResolution = "q"
 )
 
-func newRtcpThrottle(conf config.RTCPThrottleConfig) *rtcpThrottle {
-	return &rtcpThrottle{
+func newPLIThrottle(conf config.PLIThrottleConfig) *pliThrottle {
+	return &pliThrottle{
 		config:    conf,
 		throttles: make(map[uint32]func(func())),
 	}
 }
 
-func (t *rtcpThrottle) addTrack(ssrc uint32, rid string) {
+func (t *pliThrottle) addTrack(ssrc uint32, rid string) {
 	t.mu.Lock()
 	defer t.mu.Unlock()
 
@@ -48,7 +48,7 @@ func (t *rtcpThrottle) addTrack(ssrc uint32, rid string) {
 	t.throttles[ssrc] = throttle.New(duration)
 }
 
-func (t *rtcpThrottle) add(ssrc uint32, f func()) {
+func (t *pliThrottle) add(ssrc uint32, f func()) {
 	t.mu.RLock()
 	defer t.mu.RUnlock()
 
@@ -57,7 +57,7 @@ func (t *rtcpThrottle) add(ssrc uint32, f func()) {
 	}
 }
 
-func (t *rtcpThrottle) removeTrack(ssrc uint32) {
+func (t *pliThrottle) removeTrack(ssrc uint32) {
 	t.mu.Lock()
 	defer t.mu.Unlock()
 
@@ -67,7 +67,7 @@ func (t *rtcpThrottle) removeTrack(ssrc uint32) {
 	}
 }
 
-func (t *rtcpThrottle) close() {
+func (t *pliThrottle) close() {
 	t.mu.Lock()
 	defer t.mu.Unlock()
 

pkg/service/roommanager.go

@@ -261,7 +261,7 @@ func (r *RoomManager) StartSession(roomName string, pi routing.ParticipantInit,
 		AudioConfig:     r.config.Audio,
 		ProtocolVersion: pv,
 		Stats:           room.GetStatsReporter(),
-		ThrottleConfig:  r.config.RTC.Throttle,
+		ThrottleConfig:  r.config.RTC.PLIThrottle,
 	})
 	if err != nil {
 		logger.Errorw("could not create participant", err)