Perf: Avoid RTP packet copy for publisher NACK.

trunk/src/app/srs_app_rtc_conn.cpp

@@ -924,15 +924,6 @@ srs_error_t SrsRtcPublishStream::initialize(SrsRequest* r, SrsRtcStreamDescripti
 
     srs_trace("RTC publisher nack=%d, pt-drop=%u, twcc=%u/%d", nack_enabled_, pt_to_drop_, twcc_enabled_, twcc_id);
 
-    for (vector<SrsRtcAudioRecvTrack*>::iterator it = audio_tracks_.begin(); it != audio_tracks_.end(); ++it) {
-        SrsRtcAudioRecvTrack* track = *it;
-        track->set_nack_enabled(nack_enabled_);
-    }
-    for (vector<SrsRtcVideoRecvTrack*>::iterator it = video_tracks_.begin(); it != video_tracks_.end(); ++it) {
-        SrsRtcVideoRecvTrack* track = *it;
-        track->set_nack_enabled(nack_enabled_);
-    }
-
     // Update stat for session.
     session_->stat_->nn_publishers++;
 
@@ -1162,6 +1153,8 @@ srs_error_t SrsRtcPublishStream::on_rtp_plaintext(char* plaintext, int nb_plaint
 
     // Handle the packet.
     SrsBuffer buf(p, nb_plaintext);
+
+    // @remark Note that the pkt might be set to NULL.
     err = do_on_rtp_plaintext(pkt, &buf);
 
     // Release the packet to cache.
@@ -1170,7 +1163,7 @@ srs_error_t SrsRtcPublishStream::on_rtp_plaintext(char* plaintext, int nb_plaint
     return err;
 }
 
-srs_error_t SrsRtcPublishStream::do_on_rtp_plaintext(SrsRtpPacket2* pkt, SrsBuffer* buf)
+srs_error_t SrsRtcPublishStream::do_on_rtp_plaintext(SrsRtpPacket2*& pkt, SrsBuffer* buf)
 {
     srs_error_t err = srs_success;
 
@@ -1206,6 +1199,20 @@ srs_error_t SrsRtcPublishStream::do_on_rtp_plaintext(SrsRtpPacket2* pkt, SrsBuff
         }
     }
 
+    // For NACK to handle packet.
+    // @remark Note that the pkt might be set to NULL.
+    if (nack_enabled_) {
+        if (audio_track) {
+            if ((err = audio_track->on_nack(&pkt)) != srs_success) {
+                return srs_error_wrap(err, "on nack");
+            }
+        } else if (video_track) {
+            if ((err = video_track->on_nack(&pkt)) != srs_success) {
+                return srs_error_wrap(err, "on nack");
+            }
+        }
+    }
+
     return err;
 }
 

trunk/src/app/srs_app_rtc_conn.hpp

@@ -325,7 +325,7 @@ private:
     // @remark We copy the plaintext, user should free it.
     srs_error_t on_rtp_plaintext(char* plaintext, int nb_plaintext);
 private:
-    srs_error_t do_on_rtp_plaintext(SrsRtpPacket2* pkt, SrsBuffer* buf);
+    srs_error_t do_on_rtp_plaintext(SrsRtpPacket2*& pkt, SrsBuffer* buf);
 public:
     srs_error_t check_send_nacks();
 public:

trunk/src/app/srs_app_rtc_source.cpp

@@ -1729,7 +1729,6 @@ SrsRtcRecvTrack::SrsRtcRecvTrack(SrsRtcConnection* session, SrsRtcTrackDescripti
     session_ = session;
     track_desc_ = track_desc->copy();
     statistic_ = new SrsRtcTrackStatistic();
-    nack_enabled_ = false;
 
     if (is_audio) {
         rtp_queue_ = new SrsRtpRingBuffer(100);
@@ -1750,11 +1749,6 @@ SrsRtcRecvTrack::~SrsRtcRecvTrack()
     srs_freep(statistic_);
 }
 
-void SrsRtcRecvTrack::set_nack_enabled(bool v)
-{
-    nack_enabled_ = v;
-}
-
 bool SrsRtcRecvTrack::has_ssrc(uint32_t ssrc)
 {
     return track_desc_->has_ssrc(ssrc);
@@ -1818,10 +1812,11 @@ std::string SrsRtcRecvTrack::get_track_id()
     return track_desc_->id_;
 }
 
-srs_error_t SrsRtcRecvTrack::on_nack(SrsRtpPacket2* pkt)
+srs_error_t SrsRtcRecvTrack::on_nack(SrsRtpPacket2** ppkt)
 {
     srs_error_t err = srs_success;
 
+    SrsRtpPacket2* pkt = *ppkt;
     uint16_t seq = pkt->header.get_sequence();
     SrsRtpNackInfo* nack_info = nack_receiver_->find(seq);
     if (nack_info) {
@@ -1842,7 +1837,9 @@ srs_error_t SrsRtcRecvTrack::on_nack(SrsRtpPacket2* pkt)
     }
 
     // insert into video_queue and audio_queue
-    rtp_queue_->set(seq, pkt->copy());
+    // We directly use the pkt, never copy it, so we should set the pkt to NULL.
+    rtp_queue_->set(seq, pkt);
+    *ppkt = NULL;
 
     return err;
 }
@@ -1893,11 +1890,6 @@ srs_error_t SrsRtcAudioRecvTrack::on_rtp(SrsRtcStream* source, SrsRtpPacket2* pk
         return srs_error_wrap(err, "source on rtp");
     }
 
-    // For NACK to handle packet.
-    if (nack_enabled_ && (err = on_nack(pkt)) != srs_success) {
-        return srs_error_wrap(err, "on nack");
-    }
-
     return err;
 }
 
@@ -1961,11 +1953,6 @@ srs_error_t SrsRtcVideoRecvTrack::on_rtp(SrsRtcStream* source, SrsRtpPacket2* pk
         return srs_error_wrap(err, "source on rtp");
     }
 
-    // For NACK to handle packet.
-    if (nack_enabled_ && (err = on_nack(pkt)) != srs_success) {
-        return srs_error_wrap(err, "on nack");
-    }
-
     return err;
 }
 

trunk/src/app/srs_app_rtc_source.hpp

@@ -510,9 +510,6 @@ public:
 class SrsRtcRecvTrack
 {
 protected:
-    // Whether enabled nack.
-    bool nack_enabled_;
-
     SrsRtcTrackDescription* track_desc_;
     SrsRtcTrackStatistic* statistic_;
 
@@ -527,7 +524,6 @@ public:
     SrsRtcRecvTrack(SrsRtcConnection* session, SrsRtcTrackDescription* stream_descs, bool is_audio);
     virtual ~SrsRtcRecvTrack();
 public:
-    void set_nack_enabled(bool v);
     bool has_ssrc(uint32_t ssrc);
     uint32_t get_ssrc();
     void update_rtt(int rtt);
@@ -537,8 +533,10 @@ public:
     bool set_track_status(bool active);
     bool get_track_status();
     std::string get_track_id();
-protected:
+public:
-    srs_error_t on_nack(SrsRtpPacket2* pkt);
+    // Note that we can set the pkt to NULL to avoid copy, for example, if the NACK cache the pkt and
+    // set to NULL, nack nerver copy it but set the pkt to NULL.
+    srs_error_t on_nack(SrsRtpPacket2** ppkt);
 public:
     virtual srs_error_t on_rtp(SrsRtcStream* source, SrsRtpPacket2* pkt) = 0;
     virtual srs_error_t check_send_nacks() = 0;