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>

benchmarks/scripts/utils/save_prof_sweep.sh

@@ -0,0 +1,63 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+# Save a short profiler sweep into docs/benchmarks/<YYYYMMDD_HHMMSS>/
+# Usage: scripts/save_prof_sweep.sh [-d SEC] [-t CSV] [-s N]
+
+RUNTIME=2
+THREADS="1,4"
+SAMPLE_N=8
+BENCH_TIMEOUT=""
+KILL_GRACE=${KILL_GRACE:-2}
+
+while getopts ":d:t:s:h" opt; do
+  case $opt in
+    d) RUNTIME="$OPTARG" ;;
+    t) THREADS="$OPTARG" ;;
+    s) SAMPLE_N="$OPTARG" ;;
+    h) echo "Usage: $0 [-d SEC] [-t CSV] [-s N]"; exit 0 ;;
+    :) echo "Missing arg -$OPTARG"; exit 2 ;;
+    *) echo "Usage: $0 [-d SEC] [-t CSV] [-s N]"; exit 2 ;;
+  esac
+done
+
+ROOT_DIR="$(cd "$(dirname "$0")/.." && pwd)"
+OUTDIR="$ROOT_DIR/docs/benchmarks/$(date +%Y%m%d_%H%M%S)"
+mkdir -p "$OUTDIR"
+
+LIB="$(readlink -f "$ROOT_DIR/libhakmem.so" || true)"
+LARSON="$ROOT_DIR/mimalloc-bench/bench/larson/larson"
+
+if [[ -z "${BENCH_TIMEOUT}" ]]; then
+  BENCH_TIMEOUT=$(( RUNTIME + 3 ))
+fi
+
+echo "Saving sweep into: $OUTDIR" | tee "$OUTDIR/summary.txt"
+echo "RUNTIME=$RUNTIME THREADS=$THREADS SAMPLE=1/$((1<<SAMPLE_N)) TIMEOUT=${BENCH_TIMEOUT}s" | tee -a "$OUTDIR/summary.txt"
+
+declare -a RUNS=(
+  "tiny 8 1024"
+  "mid 2048 32768"
+  "gap 33000 65536"
+  "large 65536 1048576"
+)
+
+IFS=',' read -r -a TARR <<< "$THREADS"
+
+for r in "${RUNS[@]}"; do
+  read -r name rmin rmax <<< "$r"
+  for t in "${TARR[@]}"; do
+    label="${name}_T${t}_${rmin}-${rmax}"
+    echo "== $label ==" | tee -a "$OUTDIR/summary.txt"
+    if [[ -f "$LARSON" && -f "$ROOT_DIR/libhakmem.so" ]]; then
+      timeout -k "${KILL_GRACE}s" "${BENCH_TIMEOUT}s" \
+        env HAKMEM_PROF=1 HAKMEM_PROF_SAMPLE="$SAMPLE_N" \
+        LD_PRELOAD="$LIB" "$LARSON" "$RUNTIME" "$rmin" "$rmax" 10000 1 12345 "$t" 2>&1 \
+        | tee "$OUTDIR/${label}.log" | tail -n 80 | tee -a "$OUTDIR/summary.txt"
+    else
+      echo "Skip: missing larson or libhakmem.so" | tee -a "$OUTDIR/summary.txt"
+    fi
+  done
+done
+
+echo "Done. See $OUTDIR" | tee -a "$OUTDIR/summary.txt"