- Explore a structural MT executor change that reduces per-step handoff overhead without simply retuning constants: e.g. adaptive linger/search by recent epoch cadence, or a quiescent-hot state that avoids full park/unpark churn while preserving pool active-bit invariants.
- Inspect simulation hot paths beyond the executor, especially TCP ACK/timer bookkeeping and FIFO port scheduling, since the sim-wall metric excludes routing/setup and nearby executor retunes have all lost.