#include <stdio.h>
#include <stdlib.h>

int main() {
    printf("=== Deep Analysis: The Real 24-byte Mystery ===\n\n");
    
    // Key insight: aligned_alloc() test showed ONLY 1.5 MB for 100 × 64KB
    // Expected: 6.4 MB
    // This means: RSS is NOT tracking all virtual memory!
    
    printf("Observation from aligned_alloc test:\n");
    printf("  100 × 64 KB = 6.4 MB expected\n");
    printf("  Actual RSS: 1.5 MB\n");
    printf("  Ratio: 23%% (only touched pages counted!)\n\n");
    
    printf("HAKMEM test results:\n");
    printf("  1M × 16B = 15.26 MB data\n");
    printf("  RSS: 39.6 MB\n");
    printf("  Overhead: 24.34 MB\n\n");
    
    printf("Hypothesis: SuperSlab pre-allocation\n");
    printf("  SuperSlab size: 2 MB\n");
    printf("  Blocks per slab (16B): 4096\n");
    printf("  If using SuperSlab:\n");
    printf("    - Each SuperSlab: 2 MB (32 × 64 KB slabs)\n");
    printf("    - Slabs needed: 245 regular OR 8 SuperSlabs\n");
    printf("    - SuperSlab total: 8 × 2 MB = 16 MB\n\n");
    
    printf("But wait! SuperSlab would HELP, not hurt!\n\n");
    
    printf("Alternative: The TLS Magazine is FILLING UP\n");
    printf("  TLS Magazine capacity: 2048 items per class\n");
    printf("  At steady state (1M allocations active):\n");
    printf("    - Magazine likely has ~1000-2000 items cached\n");
    printf("    - These are ALLOCATED blocks held in magazine\n");
    printf("    - 2048 × 16B × 8 classes = 256 KB\n");
    printf("  But that's only 0.25 MB, not 24 MB!\n\n");
    
    printf("REAL ROOT CAUSE: Working Set Effect\n");
    printf("  The test allocates 1M × 16B sequentially\n");
    printf("  RSS measures: Data + Pointer array + ALL touched pages\n\n");
    
    printf("Let's recalculate with page granularity:\n");
    printf("  Page size: 4 KB\n");
    printf("  Slab size: 64 KB = 16 pages\n");
    printf("  Slabs needed: 245\n");
    printf("  Total pages touched: 245 × 16 = 3920 pages\n");
    printf("  Total RSS from slabs: 3920 × 4 KB = 15.31 MB ✓\n\n");
    
    printf("But actual RSS = 39.6 MB, so where's the other 24 MB?\n\n");
    
    printf("=== THE ANSWER ===\n");
    printf("It's NOT the slabs! It's something else entirely.\n\n");
    
    printf("Checking test_memory_usage.c:\n");
    printf("  void** ptrs = malloc(1M × 8 bytes);\n");
    printf("  1M allocations × 16 bytes each\n");
    printf("  BUT: Each malloc has HEADER overhead!\n\n");
    
    printf("Standard malloc overhead:\n");
    printf("  glibc malloc: 8-16 bytes per allocation\n");
    printf("  If glibc adds 16 bytes per block:\n");
    printf("    1M × (16 data + 16 header) = 32 MB\n");
    printf("  Plus pointer array: 7.63 MB\n");
    printf("  Total: 39.63 MB ✓✓✓\n\n");
    
    printf("CONCLUSION:\n");
    printf("The 24-byte overhead is HAKMEM's OWN block headers!\n");
    printf("But wait... HAKMEM uses bitmap, not headers!\n\n");
    
    printf("Let me check if test is calling glibc malloc underneath...\n");
    
    return 0;
}