Commit Graph

54 Commits

Author SHA1 Message Date
602edab87f Phase 1: Box Theory refactoring + include reduction
Phase 1-1: Split hakmem_tiny_free.inc (1,711 → 452 lines, -73%)
- Created tiny_free_magazine.inc.h (413 lines) - Magazine layer
- Created tiny_superslab_alloc.inc.h (394 lines) - SuperSlab alloc
- Created tiny_superslab_free.inc.h (305 lines) - SuperSlab free

Phase 1-2++: Refactor hakmem_pool.c (1,481 → 907 lines, -38.8%)
- Created pool_tls_types.inc.h (32 lines) - TLS structures
- Created pool_mf2_types.inc.h (266 lines) - MF2 data structures
- Created pool_mf2_helpers.inc.h (158 lines) - Helper functions
- Created pool_mf2_adoption.inc.h (129 lines) - Adoption logic

Phase 1-3: Reduce hakmem_tiny.c includes (60 → 46, -23.3%)
- Created tiny_system.h - System headers umbrella (stdio, stdlib, etc.)
- Created tiny_api.h - API headers umbrella (stats, query, rss, registry)

Performance: 4.19M ops/s maintained (±0% regression)
Verified: Larson benchmark 2×8×128×1024 = 4,192,128 ops/s

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

Co-Authored-By: Claude <noreply@anthropic.com>
2025-11-06 21:54:12 +09:00
5ea6c1237b Tiny: add per-class refill count tuning infrastructure (ChatGPT)
External AI (ChatGPT Pro) implemented hierarchical refill count tuning:
- Move getenv() from hot path to init (performance hygiene)
- Add per-class granularity: global → hot/mid → per-class precedence
- Environment variables:
  * HAKMEM_TINY_REFILL_COUNT (global default)
  * HAKMEM_TINY_REFILL_COUNT_HOT (classes 0-3)
  * HAKMEM_TINY_REFILL_COUNT_MID (classes 4-7)
  * HAKMEM_TINY_REFILL_COUNT_C{0..7} (per-class override)

Performance impact: Neutral (no tuning applied yet, default=16)
- Larson 4-thread: 4.19M ops/s (unchanged)
- No measurable overhead from init-time parsing

Code quality improvement:
- Better separation: hot path reads plain ints (no syscalls)
- Future-proof: enables A/B testing per size class
- Documentation: ENV_VARS.md updated

Note: Per Ultrathink's advice, further tuning deferred until bottleneck
visualization (superslab_refill branch analysis) is complete.

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

Co-Authored-By: Claude <noreply@anthropic.com>
Co-Authored-By: ChatGPT <external-ai@openai.com>
2025-11-05 17:45:11 +09:00
6550cd3970 Remove overhead: diagnostic + counters for fast path
### Changes:
1. **Removed diagnostic from wrapper** (hakmem_tiny.c:1542)
   - Was: getenv() + fprintf() on every wrapper call
   - Now: Direct return tiny_alloc_fast(size)
   - Relies on LTO (-flto) for inlining

2. **Removed counter overhead from malloc()** (hakmem.c:1242)
   - Was: 4 TLS counter increments per malloc
     - g_malloc_total_calls++
     - g_malloc_tiny_size_match++
     - g_malloc_fast_path_tried++
     - g_malloc_fast_path_null++ (on miss)
   - Now: Zero counter overhead

### Performance Results:
```
Before (with overhead):  1.51M ops/s
After (zero overhead):   1.59M ops/s  (+5% 🎉)
Baseline (old impl):     1.68M ops/s  (-5% gap remains)
System malloc:           8.08M ops/s  (reference)
```

### Analysis:
**What was heavy:**
- Counter increments: ~4 TLS writes per malloc (cache pollution)
- Diagnostic: getenv() + fprintf() check (even if disabled)
- These added ~80K ops/s overhead

**Remaining gap (-5% vs baseline):**
Box Theory (1.59M) vs Old implementation (1.68M)
- Likely due to: ownership check in free path
- Or: refill backend (sll_refill_small_from_ss vs hak_tiny_alloc x16)

### Bottleneck Update:
From profiling data (2,418 cycles per fast path):
```
Fast path time: 49.5M cycles (49.1% of total)
Refill time:    51.3M cycles (50.9% of total)

Counter overhead removed: ~5% improvement
LTO should inline wrapper: Further gains expected
```

### Status:
 IMPROVEMENT - Removed overhead, 5% faster
 STILL SHORT - 5% slower than baseline (1.68M target)

### Next Steps:
A. Investigate ownership check overhead in free path
B. Compare refill backend efficiency
C. Consider reverting to old implementation if gap persists

Related: LARSON_PERFORMANCE_ANALYSIS_2025_11_05.md
2025-11-05 06:25:29 +00:00
52386401b3 Debug Counters Implementation - Clean History
Major Features:
- Debug counter infrastructure for Refill Stage tracking
- Free Pipeline counters (ss_local, ss_remote, tls_sll)
- Diagnostic counters for early return analysis
- Unified larson.sh benchmark runner with profiles
- Phase 6-3 regression analysis documentation

Bug Fixes:
- Fix SuperSlab disabled by default (HAKMEM_TINY_USE_SUPERSLAB)
- Fix profile variable naming consistency
- Add .gitignore patterns for large files

Performance:
- Phase 6-3: 4.79 M ops/s (has OOM risk)
- With SuperSlab: 3.13 M ops/s (+19% improvement)

This is a clean repository without large log files.

🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude <noreply@anthropic.com>
2025-11-05 12:31:14 +09:00