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VerseVDI-Data-Plane/openspec/changes/truthful-fixed-frame-qualification/proposal.md
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sechmachine 122080ab34
Verify Data Plane / gateway (push) Failing after 3m59s
fix(gateway): recover bounded pacing debt
2026-08-09 20:54:15 +07:00

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Markdown

## Why
The existing fixed-profile harness treats each 1,179-byte datagram as an encoded frame, so its reported frame rate, frame boundaries, bitrate, queue pressure, and processing evidence do not model the named 60/120 FPS profiles.
The v6 complete-frame fixture subsequently exposed a source-fidelity defect on ordinary Linux runners: it emitted every UDP shard in one tight loop, unlike pinned Apollo's bounded intra-frame rate and batch schedule. The affected v6 qualification evidence remains retained but is superseded for candidate-readiness purposes.
Private Linux run 125 then demonstrated a separate production-ingress defect after source pacing was corrected: 33 successful fixture writes missing from `MediaIngress` matched 33 measured kernel UDP drops while decrypt/FEC, queue, pacer, QUIC, and client counters remained downstream of the shortfall.
The consumed v8 Section 7 attempt at `55afea72` subsequently failed after accumulated host scheduling delays exposed the production pacer's discarded schedule debt beyond its 5 ms instantaneous catch-up allowance. The retained partial evidence remains failed and supersedes `55afea72` as a final executable candidate.
## What Changes
- Generate deterministic variable-size encoded frame units at the named frame rates and target bitrates, including bounded keyframes.
- Traverse native Apollo recovery, production queues, the production pacer, QUIC framing, and independent reassembly.
- Assert frame count/rate, bitrate, exact bytes and boundaries, clean loss attribution, latency, and resource bounds.
- Decouple native video socket draining from the single decrypt/FEC processor with a fixed provider-scoped receive pool and request the source-backed video receive-buffer size.
- Retain bounded valid per-flow pacing debt after a host stall and repay it at no more than 5% above nominal fair share.
- Keep short smoke tests separate and leave all prior normative artifacts unchanged.
## Capabilities
### New Capabilities
None.
### Modified Capabilities
- `gateway-qualification`: Fixed-profile evidence measures complete encoded frame units rather than one datagram per frame.
## Impact
The qualification harness, its canonical specification, native Apollo video ingress in `gateway/apollo_native.go`, and the existing production fair pacer in `gateway/telemetry.go`. Downstream complete-frame queues, audio/control ingress, codec/FEC formats, QUIC, dependencies, and public interfaces remain unchanged. No codec operation or normative rerun is included. Requirements: P3C-002, P3C-008, P3C-029, P3C-030, P3C-033, VER-009, VER-010, OPS-015.