1.7 KiB
1.7 KiB
Context
FragmentPayload currently stops at 16 × 1,179 bytes and the independent test client assumes ordered fragments. Native Apollo output enters count-only buffered channels, so realistic complete frames have neither a byte ceiling nor an explicit residence bound.
Goals / Non-Goals
Goals:
- Implement Protocol datagram-v2 for complete encoded frames up to 1 MiB.
- Reassemble bounded duplicate/reordered QUIC datagrams independently.
- Bound native video queue count, bytes, and residence time while retaining latest-frame replacement and drop telemetry.
Non-Goals:
- Codec inspection, retransmission, provider fallback, generic queue/transport APIs, or Server behavior changes.
Decisions
- Keep the existing
Frame/QUIC path and add version-aware encode/decode rather than a second transport. - Use one sequence per provider frame and the Protocol 1,177-byte fragment size.
- Keep the existing native video channel at 16 entries, add exact atomic byte accounting capped at 4 MiB, and use per-entry timers for the 250 ms residence bound. This matches the Protocol's reviewed incomplete-unit timeout and covers bounded keyframe serialization; the transport performs a final stale check.
- Audio and events keep their independent existing limits.
Risks / Trade-offs
- [Latest-frame eviction drops decodable dependencies] → preserve truthful drops and existing IDR feedback; never grow memory or block every session.
- [Large frames multiply fragment sends] → cap both complete bytes and fragment count before allocation.
- [Expiry races with dequeue or cleanup] → stop each package-private timer on dequeue/replacement, serialize channel expiry and close, and retain the transport stale check.