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7 Commits

Author SHA1 Message Date
Moe Charm (CI)
72b38bc994 Phase E3-FINAL: Fix Box API offset bugs - ALL classes now use correct offsets 
## Root Cause Analysis (GPT5)

**Physical Layout Constraints**:
- Class 0: 8B = [1B header][7B payload] → offset 1 = 9B needed = ❌ IMPOSSIBLE
- Class 1-6: >=16B = [1B header][15B+ payload] → offset 1 = ✅ POSSIBLE
- Class 7: 1KB → offset 0 (compatibility)

**Correct Specification**:
- HAKMEM_TINY_HEADER_CLASSIDX != 0:
  - Class 0, 7: next at offset 0 (overwrites header when on freelist)
  - Class 1-6: next at offset 1 (after header)
- HAKMEM_TINY_HEADER_CLASSIDX == 0:
  - All classes: next at offset 0

**Previous Bug**:
- Attempted "ALL classes offset 1" unification
- Class 0 with offset 1 caused immediate SEGV (9B > 8B block size)
- Mixed 2-arg/3-arg API caused confusion

## Fixes Applied

### 1. Restored 3-Argument Box API (core/box/tiny_next_ptr_box.h)
```c
// Correct signatures
void tiny_next_write(int class_idx, void* base, void* next_value)
void* tiny_next_read(int class_idx, const void* base)

// Correct offset calculation
size_t offset = (class_idx == 0 || class_idx == 7) ? 0 : 1;
```

### 2. Updated 123+ Call Sites Across 34 Files
- hakmem_tiny_hot_pop_v4.inc.h (4 locations)
- hakmem_tiny_fastcache.inc.h (3 locations)
- hakmem_tiny_tls_list.h (12 locations)
- superslab_inline.h (5 locations)
- tiny_fastcache.h (3 locations)
- ptr_trace.h (macro definitions)
- tls_sll_box.h (2 locations)
- + 27 additional files

Pattern: `tiny_next_read(base)` → `tiny_next_read(class_idx, base)`
Pattern: `tiny_next_write(base, next)` → `tiny_next_write(class_idx, base, next)`

### 3. Added Sentinel Detection Guards
- tiny_fast_push(): Block nodes with sentinel in ptr or ptr->next
- tls_list_push(): Block nodes with sentinel in ptr or ptr->next
- Defense-in-depth against remote free sentinel leakage

## Verification (GPT5 Report)

**Test Command**: `./out/release/bench_random_mixed_hakmem --iterations=70000`

**Results**:
- ✅ Main loop completed successfully
- ✅ Drain phase completed successfully
- ✅ NO SEGV (previous crash at iteration 66151 is FIXED)
- ℹ️ Final log: "tiny_alloc(1024) failed" is normal fallback to Mid/ACE layers

**Analysis**:
- Class 0 immediate SEGV: ✅ RESOLVED (correct offset 0 now used)
- 66K iteration crash: ✅ RESOLVED (offset consistency fixed)
- Box API conflicts: ✅ RESOLVED (unified 3-arg API)

## Technical Details

### Offset Logic Justification
```
Class 0:  8B block → next pointer (8B) fits ONLY at offset 0
Class 1: 16B block → next pointer (8B) fits at offset 1 (after 1B header)
Class 2: 32B block → next pointer (8B) fits at offset 1
...
Class 6: 512B block → next pointer (8B) fits at offset 1
Class 7: 1024B block → offset 0 for legacy compatibility
```

### Files Modified (Summary)
- Core API: `box/tiny_next_ptr_box.h`
- Hot paths: `hakmem_tiny_hot_pop*.inc.h`, `tiny_fastcache.h`
- TLS layers: `hakmem_tiny_tls_list.h`, `hakmem_tiny_tls_ops.h`
- SuperSlab: `superslab_inline.h`, `tiny_superslab_*.inc.h`
- Refill: `hakmem_tiny_refill.inc.h`, `tiny_refill_opt.h`
- Free paths: `tiny_free_magazine.inc.h`, `tiny_superslab_free.inc.h`
- Documentation: Multiple Phase E3 reports

## Remaining Work

None for Box API offset bugs - all structural issues resolved.

Future enhancements (non-critical):
- Periodic `grep -R '*(void**)' core/` to detect direct pointer access violations
- Enforce Box API usage via static analysis
- Document offset rationale in architecture docs

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

Co-Authored-By: Claude <noreply@anthropic.com>
 2025-11-13 06:50:20 +09:00
Moe Charm (CI)
8feeb63c2b release: silence runtime logs and stabilize benches 
- Fix HAKMEM_LOG gating to use  (numeric) so release builds compile out logs.
- Switch remaining prints to HAKMEM_LOG or guard with :
  - core/box/hak_core_init.inc.h (EVO sample warning, shutdown banner)
  - core/hakmem_config.c (config/feature prints)
  - core/hakmem.c (BigCache eviction prints)
  - core/hakmem_tiny_superslab.c (OOM, head init/expand, C7 init diagnostics)
  - core/hakmem_elo.c (init/evolution)
  - core/hakmem_batch.c (init/flush/stats)
  - core/hakmem_ace.c (33KB route diagnostics)
  - core/hakmem_ace_controller.c (ACE logs macro → no-op in release)
  - core/hakmem_site_rules.c (init banner)
  - core/box/hak_free_api.inc.h (unknown method error → release-gated)
- Rebuilt benches and verified quiet output for release:
  - bench_fixed_size_hakmem/system
  - bench_random_mixed_hakmem/system
  - bench_mid_large_mt_hakmem/system
  - bench_comprehensive_hakmem/system

Note: Kept debug logs available in debug builds and when explicitly toggled via env.
 2025-11-11 01:47:06 +09:00
Moe Charm (CI)
1b6624dec4 Fix debug build: gate Tiny observation snapshot in hakmem_tiny_stats.c behind HAKMEM_TINY_OBS_ENABLE to avoid incomplete TinyObsStats and missing globals. Now debug build passes, enabling C7 triage with fail‑fast guards. 2025-11-10 03:00:00 +09:00
Moe Charm (CI)
1010a961fb Tiny: fix header/stride mismatch and harden refill paths 
- Root cause: header-based class indexing (HEADER_CLASSIDX=1) wrote a 1-byte
  header during allocation, but linear carve/refill and initial slab capacity
  still used bare class block sizes. This mismatch could overrun slab usable
  space and corrupt freelists, causing reproducible SEGV at ~100k iters.

Changes
- Superslab: compute capacity with effective stride (block_size + header for
  classes 0..6; class7 remains headerless) in superslab_init_slab(). Add a
  debug-only bound check in superslab_alloc_from_slab() to fail fast if carve
  would exceed usable bytes.
- Refill (non-P0 and P0): use header-aware stride for all linear carving and
  TLS window bump operations. Ensure alignment/validation in tiny_refill_opt.h
  also uses stride, not raw class size.
- Drain: keep existing defense-in-depth for remote sentinel and sanitize nodes
  before splicing into freelist (already present).

Notes
- This unifies the memory layout across alloc/linear-carve/refill with a single
  stride definition and keeps class7 (1024B) headerless as designed.
- Debug builds add fail-fast checks; release builds remain lean.

Next
- Re-run Tiny benches (256/1024B) in debug to confirm stability, then in
  release. If any remaining crash persists, bisect with HAKMEM_TINY_P0_BATCH_REFILL=0
  to isolate P0 batch carve, and continue reducing branch-miss as planned.
 2025-11-09 18:55:50 +09:00
Moe Charm (CI)
707056b765 feat: Phase 7 + Phase 2 - Massive performance & stability improvements 
Performance Achievements:
- Tiny allocations: +180-280% (21M → 59-70M ops/s random mixed)
- Single-thread: +24% (2.71M → 3.36M ops/s Larson)
- 4T stability: 0% → 95% (19/20 success rate)
- Overall: 91.3% of System malloc average (target was 40-55%) ✓

Phase 7 (Tasks 1-3): Core Optimizations
- Task 1: Header validation removal (Region-ID direct lookup)
- Task 2: Aggressive inline (TLS cache access optimization)
- Task 3: Pre-warm TLS cache (eliminate cold-start penalty)
  Result: +180-280% improvement, 85-146% of System malloc

Critical Bug Fixes:
- Fix 64B allocation crash (size-to-class +1 for header)
- Fix 4T wrapper recursion bugs (BUG #7, #8, #10, #11)
- Remove malloc fallback (30% → 50% stability)

Phase 2a: SuperSlab Dynamic Expansion (CRITICAL)
- Implement mimalloc-style chunk linking
- Unlimited slab expansion (no more OOM at 32 slabs)
- Fix chunk initialization bug (bitmap=0x00000001 after expansion)
  Files: core/hakmem_tiny_superslab.c/h, core/superslab/superslab_types.h
  Result: 50% → 95% stability (19/20 4T success)

Phase 2b: TLS Cache Adaptive Sizing
- Dynamic capacity: 16-2048 slots based on usage
- High-water mark tracking + exponential growth/shrink
- Expected: +3-10% performance, -30-50% memory
  Files: core/tiny_adaptive_sizing.c/h (new)

Phase 2c: BigCache Dynamic Hash Table
- Migrate from fixed 256×8 array to dynamic hash table
- Auto-resize: 256 → 512 → 1024 → 65,536 buckets
- Improved hash function (FNV-1a) + collision chaining
  Files: core/hakmem_bigcache.c/h
  Expected: +10-20% cache hit rate

Design Flaws Analysis:
- Identified 6 components with fixed-capacity bottlenecks
- SuperSlab (CRITICAL), TLS Cache (HIGH), BigCache/L2.5 (MEDIUM)
- Report: DESIGN_FLAWS_ANALYSIS.md (11 chapters)

Documentation:
- 13 comprehensive reports (PHASE*.md, DESIGN_FLAWS*.md)
- Implementation guides, test results, production readiness
- Bug fix reports, root cause analysis

Build System:
- Makefile: phase7 targets, PREWARM_TLS flag
- Auto dependency generation (-MMD -MP) for .inc files

Known Issues:
- 4T stability: 19/20 (95%) - investigating 1 failure for 100%
- L2.5 Pool dynamic sharding: design only (needs 2-3 days integration)

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

Co-Authored-By: Claude <noreply@anthropic.com>
 2025-11-08 17:08:00 +09:00
Moe Charm (CI)
6b1382959c Phase 7-1 PoC: Region-ID Direct Lookup (+39%~+436% improvement!) 
Implemented ultra-fast header-based free path that eliminates SuperSlab
lookup bottleneck (100+ cycles → 5-10 cycles).

## Key Changes

1. **Smart Headers** (core/tiny_region_id.h):
   - 1-byte header before each allocation stores class_idx
   - Memory layout: [Header: 1B] [User data: N-1B]
   - Overhead: <2% average (0% for Slab[0] using wasted padding)

2. **Ultra-Fast Allocation** (core/tiny_alloc_fast.inc.h):
   - Write header at base: *base = class_idx
   - Return user pointer: base + 1

3. **Ultra-Fast Free** (core/tiny_free_fast_v2.inc.h):
   - Read class_idx from header (ptr-1): 2-3 cycles
   - Push base (ptr-1) to TLS freelist: 3-5 cycles
   - Total: 5-10 cycles (vs 500+ cycles current!)

4. **Free Path Integration** (core/box/hak_free_api.inc.h):
   - Removed SuperSlab lookup from fast path
   - Direct header validation (no lookup needed!)

5. **Size Class Adjustment** (core/hakmem_tiny.h):
   - Max tiny size: 1023B (was 1024B)
   - 1024B requests → Mid allocator fallback

## Performance Results

| Size | Baseline | Phase 7 | Improvement |
|------|----------|---------|-------------|
| 128B | 1.22M | 6.54M | **+436%** 🚀 |
| 512B | 1.22M | 1.70M | **+39%** |
| 1023B | 1.22M | 1.92M | **+57%** |

## Build & Test

Enable Phase 7:
  make HEADER_CLASSIDX=1 bench_random_mixed_hakmem

Run benchmark:
  HAKMEM_TINY_USE_SUPERSLAB=1 ./bench_random_mixed_hakmem 10000 128 1234567

## Known Issues

- 1024B requests fallback to Mid allocator (by design)
- Target 40-60M ops/s not yet reached (current: 1.7-6.5M)
- Further optimization needed (TLS capacity tuning, refill optimization)

## Credits

Design: ChatGPT Pro Ultrathink, Claude Code
Implementation: Claude Code with Task Agent Ultrathink support

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

Co-Authored-By: Claude <noreply@anthropic.com>
 2025-11-08 03:18:17 +09:00
Moe Charm (CI)
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