================================================================================
Phase 8 Comprehensive Allocator Comparison - Analysis
================================================================================

## Working Set 256 (Hot cache, Phase 7 comparison)

| Allocator      | Avg (M ops/s) | StdDev (%) | Min - Max      | vs HAKMEM |
|----------------|---------------|------------|----------------|-----------|
| HAKMEM Phase 8 |   79.2        | ± 2.4%     |  77.0 -  81.2  | 1.00x     |
| System malloc  |   86.7        | ± 1.0%     |  85.3 -  87.5  |  1.09x    |
| mimalloc       |  114.9        | ± 1.2%     | 112.5 - 116.2  |  1.45x    |

## Working Set 8192 (Realistic workload)

| Allocator      | Avg (M ops/s) | StdDev (%) | Min - Max      | vs HAKMEM |
|----------------|---------------|------------|----------------|-----------|
| HAKMEM Phase 8 |   16.5        | ± 2.5%     |  15.8 -  16.9  | 1.00x     |
| System malloc  |   57.1        | ± 1.3%     |  56.1 -  57.8  |  3.46x    |
| mimalloc       |   96.5        | ± 0.9%     |  95.5 -  97.7  |  5.85x    |

================================================================================
Performance Analysis
================================================================================

### 1. Working Set 256 (Hot Cache) Results

- HAKMEM Phase 8: 79.2 M ops/s
- System malloc:  86.7 M ops/s (1.09x faster)
- mimalloc:       114.9 M ops/s (1.45x faster)

HAKMEM is **9.4% slower** than System malloc and **45.2% slower** than mimalloc

### 2. Working Set 8192 (Realistic Workload) Results

- HAKMEM Phase 8: 16.5 M ops/s
- System malloc:  57.1 M ops/s (3.46x faster)
- mimalloc:       96.5 M ops/s (5.85x faster)

HAKMEM is **246.0% slower** than System malloc and **484.9% slower** than mimalloc

================================================================================
Critical Observations
================================================================================

### HAKMEM Performance Gap Analysis

Performance degradation from WS256 to WS8192:
- HAKMEM:   4.80x slowdown (79.2 → 16.5 M ops/s)
- System:   1.52x slowdown (86.7 → 57.1 M ops/s)
- mimalloc: 1.19x slowdown (114.9 → 96.5 M ops/s)

HAKMEM degrades **3.16x MORE** than System malloc
HAKMEM degrades **4.03x MORE** than mimalloc

### Key Issues Identified

1. **Hot Cache Performance (WS256)**:
   - HAKMEM: 79.2 M ops/s
   - Gap: -9.1% vs System, -45.8% vs mimalloc
   - Issue: Fast-path overhead (TLS drain, SuperSlab lookup)

2. **Realistic Workload Performance (WS8192)**:
   - HAKMEM: 16.5 M ops/s
   - Gap: -71.1% vs System, -83.1% vs mimalloc
   - Issue: SEVERE - SuperSlab scaling, fragmentation, TLB pressure

3. **Scalability Problem**:
   - HAKMEM loses 4.8x performance with larger working sets
   - System loses only 1.5x
   - mimalloc loses only 1.2x
   - Root cause: SuperSlab architecture doesn't scale well

================================================================================
Recommendations for Phase 9+
================================================================================

### CRITICAL PRIORITY: Fix WS8192 Performance Gap

The 71-83% performance gap at realistic working sets is UNACCEPTABLE.

**Immediate Actions Required:**

1. **Investigate SuperSlab Scaling (Phase 9)**
   - Profile: Why does performance collapse with larger working sets?
   - Hypothesis: SuperSlab lookup overhead, fragmentation, or TLB misses
   - Debug logs show 'shared_fail→legacy' messages → shared slab exhaustion

2. **Optimize Fast Path (Phase 10)**
   - Even WS256 shows 9-46% gap vs competitors
   - Profile TLS drain overhead
   - Consider reducing drain frequency or lazy draining

3. **Consider Alternative Architectures (Phase 11)**
   - Current SuperSlab model may be fundamentally flawed
   - Benchmark shows 4.8x degradation vs 1.5x for System malloc
   - May need hybrid approach: TLS fast path + different backend

4. **Specific Debug Actions**
   - Analyze '[SS_BACKEND] shared_fail→legacy' logs
   - Measure SuperSlab hit rate at different working set sizes
   - Profile cache misses and TLB misses

================================================================================
Raw Data (for reproducibility)
================================================================================

hakmem_256          : [78480676, 78099247, 77034450, 81120430, 81206714]
system_256          : [87329938, 86497843, 87514376, 85308713, 86630819]
mimalloc_256        : [115842807, 115180313, 116209200, 112542094, 114950573]
hakmem_8192         : [16504443, 15799180, 16916987, 16687009, 16582555]
system_8192         : [56095157, 57843156, 56999206, 57717254, 56720055]
mimalloc_8192       : [96824532, 96117137, 95521242, 97733856, 96327554]

================================================================================
Analysis Complete
================================================================================