1 files changed, 35 insertions, 9 deletions
diff --git a/third_party/libwebrtc/modules/pacing/pacing_controller.h b/third_party/libwebrtc/modules/pacing/pacing_controller.h
index 04e0a820f9..fe6ee737a9 100644
--- a/third_party/libwebrtc/modules/pacing/pacing_controller.h
+++ b/third_party/libwebrtc/modules/pacing/pacing_controller.h
@@ -67,11 +67,6 @@ class PacingController {
     }
   };
 
-  // Expected max pacer delay. If ExpectedQueueTime() is higher than
-  // this value, the packet producers should wait (eg drop frames rather than
-  // encoding them). Bitrate sent may temporarily exceed target set by
-  // UpdateBitrate() so that this limit will be upheld.
-  static const TimeDelta kMaxExpectedQueueLength;
   // If no media or paused, wake up at least every `kPausedProcessIntervalMs` in
   // order to send a keep-alive packet so we don't get stuck in a bad state due
   // to lack of feedback.
@@ -93,14 +88,45 @@ class PacingController {
   // the send burst interval.
   // Ex: max send burst interval = 63Kb / 10Mbit/s = 50ms.
   static constexpr DataSize kMaxBurstSize = DataSize::Bytes(63 * 1000);
-  // The pacer is allowed to send enqued packets in bursts and can build up a
-  // packet "debt" that correspond to approximately the send rate during
-  // the burst interval.
+
+  // Configuration default values.
   static constexpr TimeDelta kDefaultBurstInterval = TimeDelta::Millis(40);
+  static constexpr TimeDelta kMaxExpectedQueueLength = TimeDelta::Millis(2000);
+
+  struct Configuration {
+    // If the pacer queue grows longer than the configured max queue limit,
+    // pacer sends at the minimum rate needed to keep the max queue limit and
+    // ignore the current bandwidth estimate.
+    bool drain_large_queues = true;
+    // Expected max pacer delay. If ExpectedQueueTime() is higher than
+    // this value, the packet producers should wait (eg drop frames rather than
+    // encoding them). Bitrate sent may temporarily exceed target set by
+    // SetPacingRates() so that this limit will be upheld if
+    // `drain_large_queues` is set.
+    TimeDelta queue_time_limit = kMaxExpectedQueueLength;
+    // If the first packet of a keyframe is enqueued on a RTP stream, pacer
+    // skips forward to that packet and drops other enqueued packets on that
+    // stream, unless a keyframe is already being paced.
+    bool keyframe_flushing = false;
+    // Audio retransmission is prioritized before video retransmission packets.
+    bool prioritize_audio_retransmission = false;
+    // Configure separate timeouts per priority. After a timeout, a packet of
+    // that sort will not be paced and instead dropped.
+    // Note: to set TTL on audio retransmission,
+    // `prioritize_audio_retransmission` must be true.
+    PacketQueueTTL packet_queue_ttl;
+    // The pacer is allowed to send enqueued packets in bursts and can build up
+    // a packet "debt" that correspond to approximately the send rate during the
+    // burst interval.
+    TimeDelta send_burst_interval = kDefaultBurstInterval;
+  };
+
+  static Configuration DefaultConfiguration() { return Configuration{}; }
 
   PacingController(Clock* clock,
                    PacketSender* packet_sender,
-                   const FieldTrialsView& field_trials);
+                   const FieldTrialsView& field_trials,
+                   Configuration configuration = DefaultConfiguration());
 
   ~PacingController();