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Florian LoretanandGitHub
7818dd21b9
* fix: bound data-track buffering under downlink congestion The SFU data-track down-channel writer was constructed with targetLatency=0, which disables the buffered-amount/latency-based drop in writeUnreliable. Under subscriber downlink congestion, frames were queued unbounded and in order in the per-subscriber SCTP send buffer instead of being dropped, so end-to-end latency grew without limit and only drained once congestion cleared. This contradicts data tracks being a low-latency, lossy transport. Wire a dedicated `datachannel_data_track_target_latency` config through to both data-track writer call sites (mirroring how `datachannel_lossy_target_latency` controls the lossy publishData channel), reusing lossyDataChannelMinBufferedAmount as the drop floor. Defaults to 100ms so data tracks are latency-bounded out of the box; set to 0 to restore the previous unbounded behavior. Fixes #4666 * fix: track drained bytes on successful unreliable data channel writes writeUnreliable only called BitrateCalculator.AddBytes when a write failed, so on the common success path the calculator never received samples. As a result Bitrate() had no data and the latency-based drop threshold collapsed to the static minBufferedAmount floor, making the per-subscriber latency control (datachannel_lossy_target_latency and the new datachannel_data_track_target_latency) effectively inert. Call AddBytes after every write, matching writeReliable.