hakmem

Files

Moe Charm (CI) d0f939c2eb Phase ALLOC-GATE-SSOT-1 + ALLOC-TINY-FAST-DUALHOT-2: Structure fixes for alloc path

4 patches to eliminate allocation overhead and enable research path:

Patch 1: Extract malloc_tiny_fast_for_class(size, class_idx)
- SSOT: size→class conversion happens once in gate
- malloc_tiny_fast() becomes thin wrapper
- Foundation for eliminating duplicate lookups

Patch 2: Update tiny_alloc_gate_fast() to call *_for_class
- Pass class_idx computed in gate to malloc_tiny_fast_for_class()
- Eliminates second hak_tiny_size_to_class() call
- Impact: +1-2% expected from reduced instruction count

Patch 3: Reposition DUALHOT branch (C0-C3 only)
- Move class_idx <= 3 check outside alloc_dualhot_enabled()
- C4-C7 no longer evaluate ENV gate (even when OFF)
- Impact: Maintains neutral performance on default path

Patch 4: Probe window for ENV gate
- Tolerate early putenv() before probe window exhausted (64 calls)
- Maintains correctness for bench_profile setenv timing

A/B Results (DUALHOT=0 vs DUALHOT=1):
- Mixed median: 48.75M → 48.62M ops/s (-0.27%, neutral within variance)
- C6-heavy median: 23.24M → 23.63M ops/s (+1.68%, SSOT benefit)

Decision: ADOPT with DUALHOT default OFF (research feature)
- SSOT provides structural improvement
- No regression on default configuration
- C6-heavy shows SSOT effectiveness (+1.68%)

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>

2025-12-13 06:50:39 +09:00

fast_cache.h

Front-Direct implementation: SS→FC direct refill + SLL complete bypass

2025-11-14 05:41:49 +09:00

malloc_tiny_fast.h

Phase ALLOC-GATE-SSOT-1 + ALLOC-TINY-FAST-DUALHOT-2: Structure fixes for alloc path

2025-12-13 06:50:39 +09:00

quick_slot.h

Front-Direct implementation: SS→FC direct refill + SLL complete bypass

2025-11-14 05:41:49 +09:00

tiny_heap_v2.h

Phase ML1: Pool v1 memset 89.73% overhead 軽量化 (+15.34% improvement)