Fix data race contributing to wrong value of ended_at#868
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Fix `endedAt == startedAt` (zero duration) when all tracks are removed before `Synchronizer.End()` is called. This is a race in the egress shutdown path: track workers call `RemoveTrack` (which deletes from `p.tracks`) before the pipeline calls `End()`. When `End()` iterates participants to find `maxPTS`, the tracks map is already empty, so `maxPTS = 0` and `endedAt = startedAt`. The bug was latent before the duration inflation fix but masked by `time.Now()` fallback.
boks1971
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Mar 25, 2026
| defer p.Unlock() | ||
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| if t := p.tracks[ssrc]; t != nil { | ||
| t.Lock() |
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can we make this an API call to TrackSynchronizer. Would be good to keep locking inside that struct and just return the value.
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milos-lk
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Fix
endedAt == startedAt(zero duration) when all tracks are removed beforeSynchronizer.End()is called.This is a race in the egress shutdown path: track workers call
RemoveTrack(which deletes fromp.tracks) before the pipeline callsEnd(). WhenEnd()iterates participants to findmaxPTS, the tracks map is already empty, somaxPTS = 0andendedAt = startedAt.The bug was latent before the duration inflation fix but masked by
time.Now()fallback.