Session::poll_frame accumulates per-stage ns (recv_batch syscall, AES-GCM
open, Reassembler::push incl. FEC) into a PumpPerf drained via
take_pump_perf(); the client pump logs the split plus completed-AU
inter-arrival jitter (p50/p95/max + late count) every report window.
Gated on PUNKTFUNK_PERF — one branch per stage when off.
Smoothness previously had no metric at all (jump-to-live counters fire
seconds late), and the receive core had no attribution. First live use
pinned the 1.57 Gbps client wall on software AES-GCM (7 µs/pkt) vs
0.4 µs reassembly — see punktfunk-planning/design/throughput-beyond-1gbps.md.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
enricobuehler
0058f624a2