diff --git a/creation_time_experiment/run_creation_time.sh b/creation_time_experiment/run_creation_time.sh
new file mode 100755
index 0000000..041ff54
--- /dev/null
+++ b/creation_time_experiment/run_creation_time.sh
@@ -0,0 +1,156 @@
+#!/usr/bin/env bash
+set -euo pipefail
+LC_ALL=C
+
+ROOT_DIR=$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)
+RUN_ID=$(date +"%Y%m%d_%H%M%S")
+OUT_DIR="$ROOT_DIR/runs/$RUN_ID"
+mkdir -p "$OUT_DIR"
+
+LOG_FILE="$OUT_DIR/activity.log"
+
+log() {
+  echo "[$(date -Iseconds)] $*" | tee -a "$LOG_FILE"
+}
+
+count_processes() {
+  ls -d /proc/[0-9]* 2>/dev/null | wc -l
+}
+
+count_threads_total() {
+  awk '/^Threads:/ {sum+=$2} END {print sum+0}' /proc/[0-9]*/status 2>/dev/null || echo 0
+}
+
+get_mem_kb() {
+  awk '/^MemTotal:/ {t=$2} /^MemAvailable:/ {a=$2} END {print t" "a}' /proc/meminfo
+}
+
+sample_process_csv() {
+  local pid="$1"
+  local csv="$2"
+  local start_uptime="$3"
+  local max_seconds="$4"
+
+  local have_pidstat=0
+  if command -v pidstat >/dev/null 2>&1; then
+    have_pidstat=1
+  else
+    log "pidstat not found; install sysstat for accurate CPU sampling"
+  fi
+
+  local prev_cpu_total=0
+  local prev_cpu_idle=0
+  if [ -r /proc/stat ]; then
+    read -r _ c_user c_nice c_system c_idle c_iowait c_irq c_softirq c_steal _ _ < /proc/stat
+    prev_cpu_total=$((c_user + c_nice + c_system + c_idle + c_iowait + c_irq + c_softirq + c_steal))
+    prev_cpu_idle=$((c_idle + c_iowait))
+  fi
+
+  while kill -0 "$pid" 2>/dev/null; do
+    local now_uptime elapsed_s
+    now_uptime=$(awk '{print $1}' /proc/uptime)
+    elapsed_s=$(awk -v s="$start_uptime" -v n="$now_uptime" 'BEGIN{printf "%.3f", (n-s)}')
+
+    if [ "$max_seconds" -gt 0 ]; then
+      if awk -v e="$elapsed_s" -v m="$max_seconds" 'BEGIN{exit (e>m)?0:1}'; then
+        log "Timeout reached (${max_seconds}s), stopping PID=$pid"
+        kill -TERM "-$pid" 2>/dev/null || true
+        sleep 2
+        kill -KILL "-$pid" 2>/dev/null || true
+        break
+      fi
+    fi
+
+    local proc_count thread_total
+    proc_count=$(count_processes || echo 0)
+    thread_total=$(count_threads_total || echo 0)
+
+    local load1 load5 load15
+    read -r load1 load5 load15 _ < /proc/loadavg
+
+    local mem_total mem_avail mem_used
+    read -r mem_total mem_avail < <(get_mem_kb || echo "0 0")
+    mem_used=$((mem_total - mem_avail))
+
+    local cpu rss vsz nlwp
+    rss=$(awk '/^VmRSS:/ {print $2}' "/proc/$pid/status" 2>/dev/null || echo 0)
+    vsz=$(awk '/^VmSize:/ {print $2}' "/proc/$pid/status" 2>/dev/null || echo 0)
+    nlwp=$(awk '/^Threads:/ {print $2}' "/proc/$pid/status" 2>/dev/null || echo 0)
+    if [ "$have_pidstat" -eq 1 ]; then
+      cpu=$(pidstat -p "$pid" 1 1 2>/dev/null | awk -v p="$pid" '$1 ~ /^[0-9]/ && $3==p {print $8; exit}')
+      cpu=${cpu:-0.00}
+    else
+      cpu=0.00
+    fi
+    local stk=0 heap=0
+
+    local sys_cpu_pct=0.00
+    if [ -r /proc/stat ]; then
+      read -r _ c_user c_nice c_system c_idle c_iowait c_irq c_softirq c_steal _ _ < /proc/stat
+      local cpu_total=$((c_user + c_nice + c_system + c_idle + c_iowait + c_irq + c_softirq + c_steal))
+      local cpu_idle=$((c_idle + c_iowait))
+      local dt_total=$((cpu_total - prev_cpu_total))
+      local dt_idle=$((cpu_idle - prev_cpu_idle))
+      sys_cpu_pct=$(awk -v t="$dt_total" -v i="$dt_idle" 'BEGIN{ if (t<=0) printf "0.00"; else printf "%.2f", (100.0*(t-i))/t }')
+      prev_cpu_total=$cpu_total
+      prev_cpu_idle=$cpu_idle
+    fi
+
+    printf "%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s\n" \
+      "$(date -Iseconds)" "$elapsed_s" "$load1" "$load5" "$load15" \
+      "$mem_total" "$mem_avail" "$mem_used" "$proc_count" "$thread_total" \
+      "$pid" "$cpu" "$sys_cpu_pct" "${rss:-0}" "${vsz:-0}" "${stk:-0}" "${heap:-0}" "${nlwp:-0}" \
+      >> "$csv"
+
+    sleep 0.2
+  done
+}
+
+run_with_sampling() {
+  local name="$1"
+  local cmd="$2"
+  local csv="$3"
+  local max_seconds="$4"
+
+  log "Starting $name: $cmd"
+
+  echo "timestamp,elapsed_s,load1,load5,load15,mem_total_kb,mem_available_kb,mem_used_kb,proc_count,thread_count_total,pid,cpu_pct,sys_cpu_pct,rss_kb,vsz_kb,stack_kb,heap_kb,proc_threads" > "$csv"
+
+  local start_uptime pid
+  start_uptime=$(awk '{print $1}' /proc/uptime)
+
+  if command -v setsid >/dev/null 2>&1; then
+    setsid bash -c "$cmd" &
+    pid=$!
+  else
+    bash -c "$cmd" &
+    pid=$!
+  fi
+
+  sample_process_csv "$pid" "$csv" "$start_uptime" "$max_seconds"
+
+  set +e
+  wait "$pid"
+  local exit_code=$?
+  set -e
+
+  log "Finished $name (exit_code=$exit_code)"
+}
+
+log "Compiling creation_time"
+gcc -O2 -pthread -o "$ROOT_DIR/creation_time" "$ROOT_DIR/creation_time.c"
+
+CREATION_TIME_ITERS=${CREATION_TIME_ITERS:-"100 1000 10000"}
+CREATION_TIME_SECONDS=${CREATION_TIME_SECONDS:-60}
+
+STDOUT_LOG="$OUT_DIR/creation_time_stdout.log"
+STDERR_LOG="$OUT_DIR/creation_time_stderr.log"
+
+run_with_sampling \
+  "creation_time" \
+  "cd '$ROOT_DIR' && { for n in $CREATION_TIME_ITERS; do echo \"=== iterations=\$n ===\"; ./creation_time -n \"\$n\"; done; } >'$STDOUT_LOG' 2>'$STDERR_LOG'" \
+  "$OUT_DIR/creation_time.csv" \
+  "$CREATION_TIME_SECONDS"
+
+log "Experiment finished"
+log "Run directory: $OUT_DIR"
diff --git a/fork_bomb/run_fork_bomb.sh b/fork_bomb/run_fork_bomb.sh
new file mode 100755
index 0000000..d0a2010
--- /dev/null
+++ b/fork_bomb/run_fork_bomb.sh
@@ -0,0 +1,44 @@
+#!/usr/bin/env bash
+set -euo pipefail
+LC_ALL=C
+
+ROOT_DIR=$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)
+RUN_ID=$(date +"%Y%m%d_%H%M%S")
+OUT_DIR="$ROOT_DIR/runs/$RUN_ID"
+mkdir -p "$OUT_DIR"
+
+LOG_FILE="$OUT_DIR/activity.log"
+
+log() {
+  echo "[$(date -Iseconds)] $*" | tee -a "$LOG_FILE"
+}
+
+log "Compiling fork_bomb"
+gcc -O2 -o "$ROOT_DIR/fork_bomb" "$ROOT_DIR/fork_bomb.c"
+
+ALLOW_DANGEROUS=${ALLOW_DANGEROUS:-0}
+FORK_BOMB_SECONDS=${FORK_BOMB_SECONDS:-5}
+PROC_SAMPLE_STEP=${PROC_SAMPLE_STEP:-50}
+
+FORK_BOMB_CSV="$OUT_DIR/fork_bomb.csv"
+
+if [ "$ALLOW_DANGEROUS" -eq 1 ]; then
+  log "Starting fork_bomb (C-side logging)"
+  if command -v timeout >/dev/null 2>&1; then
+    timeout "$FORK_BOMB_SECONDS" sh -c "cd '$ROOT_DIR' && FORK_BOMB_CSV='$FORK_BOMB_CSV' PROC_SAMPLE_STEP='$PROC_SAMPLE_STEP' ./fork_bomb" || true
+  else
+    (cd "$ROOT_DIR" && FORK_BOMB_CSV="$FORK_BOMB_CSV" PROC_SAMPLE_STEP="$PROC_SAMPLE_STEP" ./fork_bomb) &
+    FB_PID=$!
+    sleep "$FORK_BOMB_SECONDS" || true
+    kill -TERM "-$FB_PID" 2>/dev/null || true
+    sleep 2
+    kill -KILL "-$FB_PID" 2>/dev/null || true
+  fi
+  pkill -f "./fork_bomb" 2>/dev/null || true
+else
+  log "Skipping fork_bomb (set ALLOW_DANGEROUS=1 to run)"
+  echo "timestamp,elapsed_s,load1,load5,load15,mem_total_kb,mem_available_kb,mem_used_kb,proc_count,thread_count_total,pid,cpu_pct,sys_cpu_pct,rss_kb,vsz_kb,stack_kb,heap_kb,proc_threads" > "$FORK_BOMB_CSV"
+fi
+
+log "Experiment finished"
+log "Run directory: $OUT_DIR"
diff --git a/pi_digits_benchmark/run_pi_digits_benchmark.sh b/pi_digits_benchmark/run_pi_digits_benchmark.sh
index ccc4017..55d1d6b 100755
--- a/pi_digits_benchmark/run_pi_digits_benchmark.sh
+++ b/pi_digits_benchmark/run_pi_digits_benchmark.sh
@@ -2,64 +2,167 @@
 set -euo pipefail
 LC_ALL=C
 
-DIR=$(cd "$(dirname "$0")" && pwd)
-cd "$DIR"
+ROOT_DIR=$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)
+RUN_ID=$(date +"%Y%m%d_%H%M%S")
+OUT_DIR="$ROOT_DIR/runs/$RUN_ID"
+mkdir -p "$OUT_DIR"
 
-gcc -O2 -pthread -o pi_digits_benchmark pi_digits_benchmark.c
+LOG_FILE="$OUT_DIR/activity.log"
 
-echo "Compiled pi_digits_benchmark"
+log() {
+  echo "[$(date -Iseconds)] $*" | tee -a "$LOG_FILE"
+}
+
+count_processes() {
+  ls -d /proc/[0-9]* 2>/dev/null | wc -l
+}
+
+count_threads_total() {
+  awk '/^Threads:/ {sum+=$2} END {print sum+0}' /proc/[0-9]*/status 2>/dev/null || echo 0
+}
+
+get_mem_kb() {
+  awk '/^MemTotal:/ {t=$2} /^MemAvailable:/ {a=$2} END {print t" "a}' /proc/meminfo
+}
+
+sample_process_csv() {
+  local pid="$1"
+  local csv="$2"
+  local start_uptime="$3"
+  local max_seconds="$4"
+
+  local have_pidstat=0
+  if command -v pidstat >/dev/null 2>&1; then
+    have_pidstat=1
+  else
+    log "pidstat not found; install sysstat for accurate CPU sampling"
+  fi
+
+  local prev_cpu_total=0
+  local prev_cpu_idle=0
+  if [ -r /proc/stat ]; then
+    read -r _ c_user c_nice c_system c_idle c_iowait c_irq c_softirq c_steal _ _ < /proc/stat
+    prev_cpu_total=$((c_user + c_nice + c_system + c_idle + c_iowait + c_irq + c_softirq + c_steal))
+    prev_cpu_idle=$((c_idle + c_iowait))
+  fi
+
+  while kill -0 "$pid" 2>/dev/null; do
+    local now_uptime elapsed_s
+    now_uptime=$(awk '{print $1}' /proc/uptime)
+    elapsed_s=$(awk -v s="$start_uptime" -v n="$now_uptime" 'BEGIN{printf "%.3f", (n-s)}')
+
+    if [ "$max_seconds" -gt 0 ]; then
+      if awk -v e="$elapsed_s" -v m="$max_seconds" 'BEGIN{exit (e>m)?0:1}'; then
+        log "Timeout reached (${max_seconds}s), stopping PID=$pid"
+        kill -TERM "-$pid" 2>/dev/null || true
+        sleep 2
+        kill -KILL "-$pid" 2>/dev/null || true
+        break
+      fi
+    fi
+
+    local proc_count thread_total
+    proc_count=$(count_processes || echo 0)
+    thread_total=$(count_threads_total || echo 0)
+
+    local load1 load5 load15
+    read -r load1 load5 load15 _ < /proc/loadavg
+
+    local mem_total mem_avail mem_used
+    read -r mem_total mem_avail < <(get_mem_kb || echo "0 0")
+    mem_used=$((mem_total - mem_avail))
+
+    local cpu rss vsz nlwp
+    rss=$(awk '/^VmRSS:/ {print $2}' "/proc/$pid/status" 2>/dev/null || echo 0)
+    vsz=$(awk '/^VmSize:/ {print $2}' "/proc/$pid/status" 2>/dev/null || echo 0)
+    nlwp=$(awk '/^Threads:/ {print $2}' "/proc/$pid/status" 2>/dev/null || echo 0)
+    if [ "$have_pidstat" -eq 1 ]; then
+      cpu=$(pidstat -p "$pid" 1 1 2>/dev/null | awk -v p="$pid" '$1 ~ /^[0-9]/ && $3==p {print $8; exit}')
+      cpu=${cpu:-0.00}
+    else
+      cpu=0.00
+    fi
+    local stk=0 heap=0
+
+    local sys_cpu_pct=0.00
+    if [ -r /proc/stat ]; then
+      read -r _ c_user c_nice c_system c_idle c_iowait c_irq c_softirq c_steal _ _ < /proc/stat
+      local cpu_total=$((c_user + c_nice + c_system + c_idle + c_iowait + c_irq + c_softirq + c_steal))
+      local cpu_idle=$((c_idle + c_iowait))
+      local dt_total=$((cpu_total - prev_cpu_total))
+      local dt_idle=$((cpu_idle - prev_cpu_idle))
+      sys_cpu_pct=$(awk -v t="$dt_total" -v i="$dt_idle" 'BEGIN{ if (t<=0) printf "0.00"; else printf "%.2f", (100.0*(t-i))/t }')
+      prev_cpu_total=$cpu_total
+      prev_cpu_idle=$cpu_idle
+    fi
+
+    printf "%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s\n" \
+      "$(date -Iseconds)" "$elapsed_s" "$load1" "$load5" "$load15" \
+      "$mem_total" "$mem_avail" "$mem_used" "$proc_count" "$thread_total" \
+      "$pid" "$cpu" "$sys_cpu_pct" "${rss:-0}" "${vsz:-0}" "${stk:-0}" "${heap:-0}" "${nlwp:-0}" \
+      >> "$csv"
+
+    sleep 0.2
+  done
+}
+
+run_with_sampling() {
+  local name="$1"
+  local cmd="$2"
+  local csv="$3"
+  local max_seconds="$4"
+
+  log "Starting $name: $cmd"
+
+  echo "timestamp,elapsed_s,load1,load5,load15,mem_total_kb,mem_available_kb,mem_used_kb,proc_count,thread_count_total,pid,cpu_pct,sys_cpu_pct,rss_kb,vsz_kb,stack_kb,heap_kb,proc_threads" > "$csv"
+
+  local start_uptime pid
+  start_uptime=$(awk '{print $1}' /proc/uptime)
+
+  if command -v setsid >/dev/null 2>&1; then
+    setsid bash -c "$cmd" &
+    pid=$!
+  else
+    bash -c "$cmd" &
+    pid=$!
+  fi
+
+  sample_process_csv "$pid" "$csv" "$start_uptime" "$max_seconds"
+
+  set +e
+  wait "$pid"
+  local exit_code=$?
+  set -e
+
+  log "Finished $name (exit_code=$exit_code)"
+}
+
+log "Compiling pi_digits_benchmark"
+gcc -O2 -pthread -o "$ROOT_DIR/pi_digits_benchmark" "$ROOT_DIR/pi_digits_benchmark.c"
 
 THREAD_COUNT=${THREAD_COUNT:-4}
 PROCESS_COUNT=${PROCESS_COUNT:-4}
 PI_DIGITS=${PI_DIGITS:-2000}
 CHUNK_SIZE=${CHUNK_SIZE:-500}
 
-RUNS_DIR="$DIR/runs"
-mkdir -p "$RUNS_DIR"
-RUN_ID=$(date +"%Y%m%d_%H%M%S")
+PI_BENCH_OUT_BASE="$OUT_DIR/pi_digits_benchmark"
 
-RESULTS_CSV="$DIR/results.csv"
-if [ ! -f "$RESULTS_CSV" ]; then
-  echo "run_id,timestamp,host,kernel,mode,worker_count,pi_digits,chunk_size,exit_code,wall_s,cpu_user_s,cpu_sys_s,cpu_pct,max_rss_kb,max_vsz_kb,agg_rss_kb,agg_vsz_kb,agg_pss_kb,mem_snapshot_s,final_output_bytes" > "$RESULTS_CSV"
-fi
+PI_THREAD_STDOUT="$OUT_DIR/pi_digits_thread_stdout.log"
+PI_THREAD_STDERR="$OUT_DIR/pi_digits_thread_stderr.log"
+PI_PROC_STDOUT="$OUT_DIR/pi_digits_process_stdout.log"
+PI_PROC_STDERR="$OUT_DIR/pi_digits_process_stderr.log"
 
-run_mode() {
-  local mode="$1"
-  local out_dir="$RUNS_DIR/${RUN_ID}_${mode}"
-  local stdout_log="$out_dir/stdout.log"
-  local stderr_log="$out_dir/stderr.log"
+run_with_sampling \
+  "pi_digits_benchmark_thread" \
+  "cd '$ROOT_DIR' && THREAD_COUNT='$THREAD_COUNT' PROCESS_COUNT='$PROCESS_COUNT' PI_DIGITS='$PI_DIGITS' CHUNK_SIZE='$CHUNK_SIZE' ./pi_digits_benchmark --mode thread --out-dir '$PI_BENCH_OUT_BASE/thread' >'$PI_THREAD_STDOUT' 2>'$PI_THREAD_STDERR'" \
+  "$OUT_DIR/pi_digits_thread.csv" \
+  0
 
-  mkdir -p "$out_dir"
+run_with_sampling \
+  "pi_digits_benchmark_process" \
+  "cd '$ROOT_DIR' && THREAD_COUNT='$THREAD_COUNT' PROCESS_COUNT='$PROCESS_COUNT' PI_DIGITS='$PI_DIGITS' CHUNK_SIZE='$CHUNK_SIZE' ./pi_digits_benchmark --mode process --out-dir '$PI_BENCH_OUT_BASE/process' >'$PI_PROC_STDOUT' 2>'$PI_PROC_STDERR'" \
+  "$OUT_DIR/pi_digits_process.csv" \
+  0
 
-  echo "Running mode=$mode out_dir=$out_dir"
-  THREAD_COUNT="$THREAD_COUNT" PROCESS_COUNT="$PROCESS_COUNT" PI_DIGITS="$PI_DIGITS" CHUNK_SIZE="$CHUNK_SIZE" \
-    ./pi_digits_benchmark --mode "$mode" --out-dir "$out_dir" >"$stdout_log" 2>"$stderr_log"
-
-  if [ -f "$out_dir/results.csv" ]; then
-    tail -n 1 "$out_dir/results.csv" >> "$RESULTS_CSV"
-  fi
-
-  echo "  stdout: $stdout_log"
-  echo "  stderr: $stderr_log"
-  echo "  results: $out_dir/results.csv"
-  echo "  workers: $out_dir/workers.csv"
-  echo "  pi output: $out_dir/pi_digits.txt"
-}
-
-MODE=${1:-both}
-case "$MODE" in
-  thread)
-    run_mode thread
-    ;;
-  process)
-    run_mode process
-    ;;
-  both)
-    run_mode thread
-    run_mode process
-    ;;
-  *)
-    echo "Usage: $0 [thread|process|both]"
-    exit 1
-    ;;
-esac
+log "Experiment finished"
+log "Run directory: $OUT_DIR"
diff --git a/thread_recursive_scaling/run_thread_recursive.sh b/thread_recursive_scaling/run_thread_recursive.sh
index 7889566..4be8ee9 100755
--- a/thread_recursive_scaling/run_thread_recursive.sh
+++ b/thread_recursive_scaling/run_thread_recursive.sh
@@ -2,119 +2,149 @@
 set -euo pipefail
 LC_ALL=C
 
-DIR=$(cd "$(dirname "$0")" && pwd)
-cd "$DIR"
-
-gcc -O2 -pthread -o thread_recursive thread_recursive.c -lm
-
-echo "Compiled thread_recursive"
-
-# Usage:
-#   ./run_thread_recursive.sh [branch] [depth] [hold_seconds]
-# Example:
-#   ./run_thread_recursive.sh 6 6 6
-
-BRANCH=${1:-6}
-DEPTH=${2:-6}
-HOLD=${3:-6}
-
-RESULTS_CSV="$DIR/results.csv"
-RUNS_DIR="$DIR/runs"
-mkdir -p "$RUNS_DIR"
-
+ROOT_DIR=$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)
 RUN_ID=$(date +"%Y%m%d_%H%M%S")
-STDOUT_LOG="$RUNS_DIR/${RUN_ID}_stdout.log"
-STDERR_LOG="$RUNS_DIR/${RUN_ID}_stderr.log"
-SAMPLE_LOG="$RUNS_DIR/${RUN_ID}_samples.csv"
+OUT_DIR="$ROOT_DIR/runs/$RUN_ID"
+mkdir -p "$OUT_DIR"
 
-if [ ! -f "$RESULTS_CSV" ]; then
-	echo "run_id,timestamp,host,kernel,branch,depth,hold_s,exit_code,wall_s,max_rss_kb,max_vsz_kb,max_threads,avg_cpu,max_cpu,total_created_threads,estimated_full_tree" > "$RESULTS_CSV"
-fi
+LOG_FILE="$OUT_DIR/activity.log"
 
-echo "Running: ./thread_recursive -b $BRANCH -d $DEPTH -s $HOLD"
+log() {
+  echo "[$(date -Iseconds)] $*" | tee -a "$LOG_FILE"
+}
 
-START_UPTIME=$(awk '{print $1}' /proc/uptime)
-./thread_recursive -b "$BRANCH" -d "$DEPTH" -s "$HOLD" >"$STDOUT_LOG" 2>"$STDERR_LOG" &
-PID=$!
+count_processes() {
+  ls -d /proc/[0-9]* 2>/dev/null | wc -l
+}
 
-echo "Sampling metrics for PID=$PID (1s interval)"
-echo "sec_from_start,cpu_pct,rss_kb,vsz_kb,nlwp" > "$SAMPLE_LOG"
+count_threads_total() {
+  awk '/^Threads:/ {sum+=$2} END {print sum+0}' /proc/[0-9]*/status 2>/dev/null || echo 0
+}
 
-MAX_RSS=0
-MAX_VSZ=0
-MAX_THR=0
-MAX_CPU=0
-SUM_CPU=0
-SAMPLE_COUNT=0
+get_mem_kb() {
+  awk '/^MemTotal:/ {t=$2} /^MemAvailable:/ {a=$2} END {print t" "a}' /proc/meminfo
+}
 
-CLK_TCK=$(getconf CLK_TCK)
-PREV_UPTIME=$(awk '{print $1}' /proc/uptime)
-PREV_TICKS=0
-if [ -r "/proc/$PID/stat" ]; then
-	PREV_TICKS=$(awk '{print $14 + $15}' "/proc/$PID/stat" 2>/dev/null || echo 0)
-fi
+sample_process_csv() {
+  local pid="$1"
+  local csv="$2"
+  local start_uptime="$3"
+  local max_seconds="$4"
 
-while kill -0 "$PID" 2>/dev/null; do
-	NOW_UPTIME=$(awk '{print $1}' /proc/uptime)
-	ELAPSED_S=$(awk -v s="$START_UPTIME" -v n="$NOW_UPTIME" 'BEGIN{printf "%.3f", (n-s)}')
+  local have_pidstat=0
+  if command -v pidstat >/dev/null 2>&1; then
+    have_pidstat=1
+  else
+    log "pidstat not found; install sysstat for accurate CPU sampling"
+  fi
 
-	if [ -r "/proc/$PID/status" ] && [ -r "/proc/$PID/stat" ]; then
-		RSS=$(awk '/^VmRSS:/ {print $2}' "/proc/$PID/status" 2>/dev/null || echo 0)
-		VSZ=$(awk '/^VmSize:/ {print $2}' "/proc/$PID/status" 2>/dev/null || echo 0)
-		NLWP=$(awk '/^Threads:/ {print $2}' "/proc/$PID/status" 2>/dev/null || echo 0)
-		CUR_TICKS=$(awk '{print $14 + $15}' "/proc/$PID/stat" 2>/dev/null || echo 0)
+  local prev_cpu_total=0
+  local prev_cpu_idle=0
+  if [ -r /proc/stat ]; then
+    read -r _ c_user c_nice c_system c_idle c_iowait c_irq c_softirq c_steal _ _ < /proc/stat
+    prev_cpu_total=$((c_user + c_nice + c_system + c_idle + c_iowait + c_irq + c_softirq + c_steal))
+    prev_cpu_idle=$((c_idle + c_iowait))
+  fi
 
-		RSS=${RSS:-0}
-		VSZ=${VSZ:-0}
-		NLWP=${NLWP:-0}
+  while kill -0 "$pid" 2>/dev/null; do
+    local now_uptime elapsed_s
+    now_uptime=$(awk '{print $1}' /proc/uptime)
+    elapsed_s=$(awk -v s="$start_uptime" -v n="$now_uptime" 'BEGIN{printf "%.3f", (n-s)}')
 
-		DT=$(awk -v a="$PREV_UPTIME" -v b="$NOW_UPTIME" 'BEGIN{print b-a}')
-		DC=$(awk -v a="$PREV_TICKS" -v b="$CUR_TICKS" 'BEGIN{print b-a}')
-		CPU=$(awk -v dt="$DT" -v dc="$DC" -v hz="$CLK_TCK" 'BEGIN{ if (dt<=0) printf "0.00"; else printf "%.2f", (100.0*dc)/(dt*hz) }')
+    if [ "$max_seconds" -gt 0 ]; then
+      if awk -v e="$elapsed_s" -v m="$max_seconds" 'BEGIN{exit (e>m)?0:1}'; then
+        log "Timeout reached (${max_seconds}s), stopping PID=$pid"
+        kill -TERM "-$pid" 2>/dev/null || true
+        sleep 2
+        kill -KILL "-$pid" 2>/dev/null || true
+        break
+      fi
+    fi
 
-		echo "$ELAPSED_S,$CPU,$RSS,$VSZ,$NLWP" >> "$SAMPLE_LOG"
+    local proc_count thread_total
+    proc_count=$(count_processes || echo 0)
+    thread_total=$(count_threads_total || echo 0)
 
-		MAX_RSS=$(awk -v a="$MAX_RSS" -v b="$RSS" 'BEGIN{print (b>a)?b:a}')
-		MAX_VSZ=$(awk -v a="$MAX_VSZ" -v b="$VSZ" 'BEGIN{print (b>a)?b:a}')
-		MAX_THR=$(awk -v a="$MAX_THR" -v b="$NLWP" 'BEGIN{print (b>a)?b:a}')
-		MAX_CPU=$(awk -v a="$MAX_CPU" -v b="$CPU" 'BEGIN{print (b>a)?b:a}')
-		SUM_CPU=$(awk -v s="$SUM_CPU" -v c="$CPU" 'BEGIN{print s+c}')
-		SAMPLE_COUNT=$((SAMPLE_COUNT + 1))
+    local load1 load5 load15
+    read -r load1 load5 load15 _ < /proc/loadavg
 
-		PREV_UPTIME=$NOW_UPTIME
-		PREV_TICKS=$CUR_TICKS
-	fi
-	sleep 1
-done
+    local mem_total mem_avail mem_used
+    read -r mem_total mem_avail < <(get_mem_kb || echo "0 0")
+    mem_used=$((mem_total - mem_avail))
 
-set +e
-wait "$PID"
-EXIT_CODE=$?
-set -e
-END_UPTIME=$(awk '{print $1}' /proc/uptime)
-WALL_S=$(awk -v s="$START_UPTIME" -v e="$END_UPTIME" 'BEGIN{printf "%.6f", (e-s)}')
+    local cpu rss vsz nlwp
+    rss=$(awk '/^VmRSS:/ {print $2}' "/proc/$pid/status" 2>/dev/null || echo 0)
+    vsz=$(awk '/^VmSize:/ {print $2}' "/proc/$pid/status" 2>/dev/null || echo 0)
+    nlwp=$(awk '/^Threads:/ {print $2}' "/proc/$pid/status" 2>/dev/null || echo 0)
+    if [ "$have_pidstat" -eq 1 ]; then
+      cpu=$(pidstat -p "$pid" 1 1 2>/dev/null | awk -v p="$pid" '$1 ~ /^[0-9]/ && $3==p {print $8; exit}')
+      cpu=${cpu:-0.00}
+    else
+      cpu=0.00
+    fi
+    local stk=0 heap=0
 
-AVG_CPU=0
-if [ "$SAMPLE_COUNT" -gt 0 ]; then
-	AVG_CPU=$(awk -v s="$SUM_CPU" -v n="$SAMPLE_COUNT" 'BEGIN{printf "%.2f", s/n}')
-fi
-MAX_CPU_FMT=$(awk -v m="$MAX_CPU" 'BEGIN{printf "%.2f", m}')
+    local sys_cpu_pct=0.00
+    if [ -r /proc/stat ]; then
+      read -r _ c_user c_nice c_system c_idle c_iowait c_irq c_softirq c_steal _ _ < /proc/stat
+      local cpu_total=$((c_user + c_nice + c_system + c_idle + c_iowait + c_irq + c_softirq + c_steal))
+      local cpu_idle=$((c_idle + c_iowait))
+      local dt_total=$((cpu_total - prev_cpu_total))
+      local dt_idle=$((cpu_idle - prev_cpu_idle))
+      sys_cpu_pct=$(awk -v t="$dt_total" -v i="$dt_idle" 'BEGIN{ if (t<=0) printf "0.00"; else printf "%.2f", (100.0*(t-i))/t }')
+      prev_cpu_total=$cpu_total
+      prev_cpu_idle=$cpu_idle
+    fi
 
-TOTAL_CREATED=$(grep -E "total_created_threads:" "$STDOUT_LOG" | awk -F': ' '{print $2}' | tail -n1)
-ESTIMATED=$(grep -E "estimated_full_tree:" "$STDOUT_LOG" | awk -F': ' '{print $2}' | tail -n1)
-TOTAL_CREATED=${TOTAL_CREATED:-NA}
-ESTIMATED=${ESTIMATED:-NA}
+    printf "%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s\n" \
+      "$(date -Iseconds)" "$elapsed_s" "$load1" "$load5" "$load15" \
+      "$mem_total" "$mem_avail" "$mem_used" "$proc_count" "$thread_total" \
+      "$pid" "$cpu" "$sys_cpu_pct" "${rss:-0}" "${vsz:-0}" "${stk:-0}" "${heap:-0}" "${nlwp:-0}" \
+      >> "$csv"
 
-TS=$(date +"%Y-%m-%dT%H:%M:%S%z")
-HOST=$(hostname)
-KERNEL=$(uname -r)
+    sleep 0.2
+  done
+}
 
-echo "$RUN_ID,$TS,$HOST,$KERNEL,$BRANCH,$DEPTH,$HOLD,$EXIT_CODE,$WALL_S,$MAX_RSS,$MAX_VSZ,$MAX_THR,$AVG_CPU,$MAX_CPU_FMT,$TOTAL_CREATED,$ESTIMATED" >> "$RESULTS_CSV"
+run_with_sampling() {
+  local name="$1"
+  local cmd="$2"
+  local csv="$3"
+  local max_seconds="$4"
 
-echo
-echo "Run complete"
-echo "  stdout: $STDOUT_LOG"
-echo "  stderr: $STDERR_LOG"
-echo "  samples: $SAMPLE_LOG"
-echo "  results csv: $RESULTS_CSV"
-echo "  exit_code=$EXIT_CODE wall_s=$WALL_S max_rss_kb=$MAX_RSS max_threads=$MAX_THR avg_cpu=$AVG_CPU max_cpu=$MAX_CPU_FMT"
+  log "Starting $name: $cmd"
+
+  echo "timestamp,elapsed_s,load1,load5,load15,mem_total_kb,mem_available_kb,mem_used_kb,proc_count,thread_count_total,pid,cpu_pct,sys_cpu_pct,rss_kb,vsz_kb,stack_kb,heap_kb,proc_threads" > "$csv"
+
+  local start_uptime pid
+  start_uptime=$(awk '{print $1}' /proc/uptime)
+
+  if command -v setsid >/dev/null 2>&1; then
+    setsid bash -c "$cmd" &
+    pid=$!
+  else
+    bash -c "$cmd" &
+    pid=$!
+  fi
+
+  sample_process_csv "$pid" "$csv" "$start_uptime" "$max_seconds"
+
+  set +e
+  wait "$pid"
+  local exit_code=$?
+  set -e
+
+  log "Finished $name (exit_code=$exit_code)"
+}
+
+log "Compiling thread_recursive"
+gcc -O2 -pthread -o "$ROOT_DIR/thread_recursive" "$ROOT_DIR/thread_recursive.c" -lm
+
+run_with_sampling \
+  "thread_recursive_scaling" \
+  "cd '$ROOT_DIR' && exec ./thread_recursive -b 6 -d 6 -s 6" \
+  "$OUT_DIR/thread_recursive_scaling.csv" \
+  0
+
+log "Experiment finished"
+log "Run directory: $OUT_DIR"