DC-PUMP-06
DC derived enforcedOrdered pump progression under backpressure. The sequence of AdmissionPeerEvents delivered to events_out is identical to the unstalled pump for the same peer input: backpressure may DELAY delivery, never REORDER it. Frames decoded from an inbound chunk are appended to ONE ordered pending_frames FIFO and dispatched exactly one per loop iteration; frames read while parked in emit_cooperative are appended to the SAME FIFO. Dispatching inline would let a deferred frame interleave ahead of a chunk's remaining frames. Keep-alive remains wire-only and emits no event (the DC-PUMP-01 emit-set stays unwidened), so replay-equivalence is preserved.
- Source
docs/clusters/LIVE-WIRE-LIVENESS/SLICE-S1-keepalive-under-backpressure.md + docs/clusters/LIVE-WIRE-LIVENESS/SLICE-S2-live-feed-reconnect.md (INV-WL-2)
Enforcement trace
Tests 1
- ce_wl_2_backpressure_preserves_event_order
Cross-references
Evidence notes
Replay-equivalence is preserved by construction: only the SCHEDULING of delivery changes, never the content or order. SUPPORTING live evidence only (never the reason for enforcement): a sustained preview run 2026-08-01 (~/.cardano-live1/ade-1376-s1s2.log) held the live tip for 8h+ with 1400 consecutive keep-alive round trips, max observed inter-line stall 20.0s (the cadence itself) against the peers ~97s limit, and recovered a deliberate docker restart of cardano-node-preview in 1m48s. Enforcement rests on the named tests + ci/ci_check_wire_liveness.sh, not on this run.