# Profiling Results (2025‑10‑22)

This document stores the current observed overheads from lightweight sampling runs. Throughput is ignored; we focus on avg ns per path.

Environment: larson, LD_PRELOAD hakmem, sampling profiler ON (HAKMEM_PROF=1), sample rates as indicated.

## 10s reference (subset)

- BURST 10s, 1T
  - tiny_alloc: avg ~28.8 ns (samples ~65k)
- BURST 10s, 4T
  - malloc_alloc: avg ~98.7 ns (samples ~16k)
- LOOP 10s, 4T
  - malloc_alloc: avg ~40.9 ns (samples ~35k)

## 2s sweep (1/256), 1T/4T (mid/large ranges)

- Mid 2–32KiB, 1T
  - ace_alloc: ~26–31 ns
  - malloc_alloc: ~150–220 ns
- Mid 2–32KiB, 4T
  - ace_alloc: ~31–35 ns
  - malloc_alloc: ~250–315 ns

- Large 64KiB–1MiB, 1T
  - ace_alloc: ~32–58 ns → 31–50 ns (after W_MAX tuning)
  - malloc_alloc: ~960–1,690 ns → 840–1,330 ns (slight drop)
- Large 64KiB–1MiB, 4T
  - ace_alloc: ~52–72 ns
  - malloc_alloc: ~2.5–4.1 µs

Notes:
- Tiny path healthy: tiny_alloc ~18–29 ns, tiny_reg_lookup ~17–23 ns.
- Registry registration ~0.6–1.3 µs (rare: slab creation only).
- Pool/L25 lock/refill present (instrumented) but low sample count in 2s runs; use focused ranges and higher sampling for deeper analysis.

## 1s sweep (1/256), 1T (W_MAX_mid=1.40, W_MAX_large=1.30)

- Mid 2–32KiB, 1T
  - ace_alloc: ~26.6 ns
  - malloc_alloc: ~153.2 ns (slight drop)
- Large 64KiB–1MiB, 1T
  - ace_alloc: ~31.9–50.6 ns
  - malloc_alloc: ~927.9–1,334.1 ns (modest drop)