hakmem/scripts/box/layout_tax_forensics_box.sh

#!/bin/bash
# Layout Tax Forensics Box
# Purpose: Compare baseline vs treatment binaries to isolate layout tax causes
# Usage: ./scripts/box/layout_tax_forensics_box.sh <baseline_binary> <treatment_binary>
# Example: ./scripts/box/layout_tax_forensics_box.sh ./bench_random_mixed_hakmem_minimal_pgo ./bench_random_mixed_hakmem_fast_pruned

set -e

BASELINE_BIN="${1:-./.bench_random_mixed_hakmem_minimal_pgo}"
TREATMENT_BIN="${2:-./.bench_random_mixed_hakmem_fast_pruned}"
ITERS=20000000
WS=400
RUNS=10
RESULT_DIR="./results/layout_tax_forensics"

# Ensure binaries exist
if [ ! -f "$BASELINE_BIN" ]; then
    echo "ERROR: Baseline binary not found: $BASELINE_BIN"
    exit 1
fi

if [ ! -f "$TREATMENT_BIN" ]; then
    echo "ERROR: Treatment binary not found: $TREATMENT_BIN"
    exit 1
fi

mkdir -p "$RESULT_DIR"

# Metrics to collect
PERF_EVENTS="cycles,instructions,branches,branch-misses,cache-misses,iTLB-loads,iTLB-load-misses,dTLB-loads,dTLB-load-misses,L1-dcache-loads,L1-dcache-load-misses,LLC-loads,LLC-load-misses"

echo "=========================================="
echo "Layout Tax Forensics Box"
echo "=========================================="
echo "Baseline binary: $BASELINE_BIN"
echo "Treatment binary: $TREATMENT_BIN"
echo "Workload: Mixed, ITERS=$ITERS, WS=$WS, RUNS=$RUNS"
echo "Metrics: $PERF_EVENTS"
echo "Output: $RESULT_DIR"
echo ""

# Throughput 10-run (baseline)
echo "=== BASELINE: Throughput (10-run) ==="
BASELINE_THROUGHPUT_FILE="$RESULT_DIR/baseline_throughput.txt"
> "$BASELINE_THROUGHPUT_FILE"
for i in $(seq 1 $RUNS); do
    # Use cleanenv to match canonical benchmark
    HAKMEM_PROFILE=MIXED_TINYV3_C7_SAFE RUNS=1 ITERS=$ITERS WS=$WS BENCH_BIN="$BASELINE_BIN" \
        bash -c 'source scripts/run_mixed_10_cleanenv.sh' 2>/dev/null | grep -oP "Throughput = +\K[0-9.]+" >> "$BASELINE_THROUGHPUT_FILE" || true
done

BASELINE_MEAN=$(awk '{sum+=$1; count++} END {print sum/count}' "$BASELINE_THROUGHPUT_FILE")
BASELINE_MEDIAN=$(sort -n "$BASELINE_THROUGHPUT_FILE" | awk 'NR==('$(($RUNS/2))')' | head -1)
BASELINE_STDDEV=$(awk -v mean="$BASELINE_MEAN" '{sum+=($1-mean)^2; count++} END {print sqrt(sum/count)}' "$BASELINE_THROUGHPUT_FILE")
BASELINE_CV=$(awk -v mean="$BASELINE_MEAN" -v sd="$BASELINE_STDDEV" 'BEGIN {print (sd/mean)*100}')

echo "Baseline throughput (M ops/s):"
cat "$BASELINE_THROUGHPUT_FILE" | nl
echo "Mean: $BASELINE_MEAN"
echo "Median: $BASELINE_MEDIAN"
echo "CV: $BASELINE_CV %"
echo ""

# Throughput 10-run (treatment)
echo "=== TREATMENT: Throughput (10-run) ==="
TREATMENT_THROUGHPUT_FILE="$RESULT_DIR/treatment_throughput.txt"
> "$TREATMENT_THROUGHPUT_FILE"
for i in $(seq 1 $RUNS); do
    HAKMEM_PROFILE=MIXED_TINYV3_C7_SAFE RUNS=1 ITERS=$ITERS WS=$WS BENCH_BIN="$TREATMENT_BIN" \
        bash -c 'source scripts/run_mixed_10_cleanenv.sh' 2>/dev/null | grep -oP "Throughput = +\K[0-9.]+" >> "$TREATMENT_THROUGHPUT_FILE" || true
done

TREATMENT_MEAN=$(awk '{sum+=$1; count++} END {print sum/count}' "$TREATMENT_THROUGHPUT_FILE")
TREATMENT_MEDIAN=$(sort -n "$TREATMENT_THROUGHPUT_FILE" | awk 'NR==('$(($RUNS/2))')' | head -1)
TREATMENT_STDDEV=$(awk -v mean="$TREATMENT_MEAN" '{sum+=($1-mean)^2; count++} END {print sqrt(sum/count)}' "$TREATMENT_THROUGHPUT_FILE")
TREATMENT_CV=$(awk -v mean="$TREATMENT_MEAN" -v sd="$TREATMENT_STDDEV" 'BEGIN {print (sd/mean)*100}')

echo "Treatment throughput (M ops/s):"
cat "$TREATMENT_THROUGHPUT_FILE" | nl
echo "Mean: $TREATMENT_MEAN"
echo "Median: $TREATMENT_MEDIAN"
echo "CV: $TREATMENT_CV %"
echo ""

# Calculate delta
DELTA=$(awk -v b="$BASELINE_MEAN" -v t="$TREATMENT_MEAN" 'BEGIN {print ((t-b)/b)*100}')
echo "Performance delta: $DELTA % ($(awk -v t="$TREATMENT_MEAN" -v b="$BASELINE_MEAN" 'BEGIN {print t-b}' | cut -c1-6)M ops/s)"
echo ""

# perf stat: single representative runs (baseline)
echo "=== BASELINE: perf stat (representative run) ==="
BASELINE_PERF_FILE="$RESULT_DIR/baseline_perf.txt"
perf stat -e "$PERF_EVENTS" -o "$BASELINE_PERF_FILE" \
    bash -c "HAKMEM_PROFILE=MIXED_TINYV3_C7_SAFE RUNS=1 ITERS=$ITERS WS=$WS BENCH_BIN='$BASELINE_BIN' source scripts/run_mixed_10_cleanenv.sh" 2>&1 || true
cat "$BASELINE_PERF_FILE"
echo ""

# perf stat: single representative runs (treatment)
echo "=== TREATMENT: perf stat (representative run) ==="
TREATMENT_PERF_FILE="$RESULT_DIR/treatment_perf.txt"
perf stat -e "$PERF_EVENTS" -o "$TREATMENT_PERF_FILE" \
    bash -c "HAKMEM_PROFILE=MIXED_TINYV3_C7_SAFE RUNS=1 ITERS=$ITERS WS=$WS BENCH_BIN='$TREATMENT_BIN' source scripts/run_mixed_10_cleanenv.sh" 2>&1 || true
cat "$TREATMENT_PERF_FILE"
echo ""

# Binary metadata
echo "=== Binary Metadata ==="
echo "Baseline:"
ls -lh "$BASELINE_BIN" | awk '{print "  Size:", $5}'
size "$BASELINE_BIN" 2>/dev/null | tail -1 || echo "  (size info not available)"
echo ""
echo "Treatment:"
ls -lh "$TREATMENT_BIN" | awk '{print "  Size:", $5}'
size "$TREATMENT_BIN" 2>/dev/null | tail -1 || echo "  (size info not available)"
echo ""

# Summary report
SUMMARY_FILE="$RESULT_DIR/layout_tax_forensics_summary.txt"
cat > "$SUMMARY_FILE" << EOF
================================================================================
Layout Tax Forensics Summary
================================================================================

Baseline:   $BASELINE_BIN
Treatment:  $TREATMENT_BIN
Workload:   Mixed (ITERS=$ITERS, WS=$WS)

THROUGHPUT RESULTS
==================
Baseline Mean:    $BASELINE_MEAN M ops/s (CV: $BASELINE_CV %)
Treatment Mean:   $TREATMENT_MEAN M ops/s (CV: $TREATMENT_CV %)
Delta:            $DELTA %

DETAILED OUTPUT
================
- Throughput samples: $BASELINE_THROUGHPUT_FILE, $TREATMENT_THROUGHPUT_FILE
- perf stat: $BASELINE_PERF_FILE, $TREATMENT_PERF_FILE

NEXT STEPS
==========
Use PHASE67A_LAYOUT_TAX_FORENSICS_SSOT.md to:
  1. Categorize delta as GO/NEUTRAL/NO-GO
  2. Map perf metrics to root causes (IPC/cache/iTLB/branch-miss)
  3. Document symptoms and remediation strategies
================================================================================
EOF

cat "$SUMMARY_FILE"
echo ""
echo "Results saved to: $RESULT_DIR"