mac-perf.sh

#!/bin/bash
# mac-perf v1.0 — On-demand macOS performance cleanup
#
# Diagnoses RAM/swap/load, kills stale dev servers and duplicate background
# processes, clears regenerable caches. Pure bash, no dependencies.
#
# Modes:
#   report      (default) — diagnose only, no kills, no deletions
#   clean       — kill stale dev servers + clear regenerable caches (safe)
#   aggressive  — also kills high-CPU dev servers + forces purge
#
# Flags:
#   --yes       — skip interactive confirmation
#   --quiet     — minimal output
#
# Examples:
#   mac-perf                    # report
#   mac-perf clean              # safe cleanup, asks for confirm
#   mac-perf clean --yes        # safe cleanup, no prompt
#   mac-perf aggressive --yes   # also kill hot dev servers + sudo purge

set -uo pipefail

MODE="${1:-report}"
shift 2>/dev/null || true
YES=0; QUIET=0
for arg in "$@"; do
  case "$arg" in
    --yes|-y) YES=1 ;;
    --quiet|-q) QUIET=1 ;;
  esac
done

# Apple Silicon page size; Intel macs are 4096
PAGE_SIZE="${MAC_PERF_PAGE_SIZE:-16384}"
LOG="${MAC_PERF_LOG:-$HOME/.mac-perf.log}"
mkdir -p "$(dirname "$LOG")" 2>/dev/null || true

log() { echo "$(date '+%Y-%m-%d %H:%M:%S') $*" >> "$LOG"; }
say() { [ "$QUIET" = 0 ] && echo "$@"; }

# ── METRICS ────────────────────────────────────────────────────────────────
available_mb() {
  vm_stat | awk -v ps="$PAGE_SIZE" '
    /Pages free/        { gsub(/\./,"",$3); f=$3+0 }
    /Pages inactive/    { gsub(/\./,"",$3); i=$3+0 }
    /Pages purgeable/   { gsub(/\./,"",$3); p=$3+0 }
    /Pages speculative/ { gsub(/\./,"",$3); s=$3+0 }
    END { printf "%d", int((f+i+p+s)*ps/1048576) }'
}
swap_used_mb() {
  sysctl vm.swapusage 2>/dev/null | awk '{for(i=1;i<=NF;i++) if($i=="used"){gsub(/\..*/,"",$(i+2)); print $(i+2)}}'
}
swap_total_mb() {
  sysctl vm.swapusage 2>/dev/null | awk '{for(i=1;i<=NF;i++) if($i=="total"){gsub(/\..*/,"",$(i+2)); print $(i+2)}}'
}
uptime_days() {
  local boot
  boot=$(sysctl -n kern.boottime 2>/dev/null | sed -n 's/.*sec = \([0-9]*\).*/\1/p')
  [ -z "$boot" ] && { echo 0; return; }
  echo $(( ($(date +%s) - boot) / 86400 ))
}
load_avg() { sysctl -n vm.loadavg | awk '{print $2}'; }

human_mb() {
  local m=$1
  if [ "$m" -gt 1024 ] 2>/dev/null; then printf "%.1fG" "$(echo "$m/1024" | bc -l)"; else echo "${m}M"; fi
}

# ── SCANNERS ───────────────────────────────────────────────────────────────
# Stale dev servers: next/vite/webpack running > 2h. Returns "pid|elapsed_min|cmd"
scan_stale_dev_servers() {
  ps -axo pid,etimes,command 2>/dev/null | awk '
    NR==1{next}
    $2+0 > 7200 {
      cmd=""; for(i=3;i<=NF;i++) cmd=cmd " "$i
      cmd=substr(cmd,2)
      if (cmd ~ /(next-server|next dev|vite|webpack-dev-server|npm run dev|bun run dev|nodemon)/ \
          && cmd !~ /grep|mac-perf/) {
        printf "%s|%d|%s\n", $1, $2/60, cmd
      }
    }'
}

# High-CPU dev servers: dev server using >50% CPU regardless of age
scan_hot_dev_servers() {
  ps -axo pid,pcpu,command 2>/dev/null | awk '
    NR==1{next}
    $2+0 > 50 {
      cmd=""; for(i=3;i<=NF;i++) cmd=cmd " "$i; cmd=substr(cmd,2)
      if (cmd ~ /(next-server|next dev|vite|webpack-dev-server|nodemon)/ \
          && cmd !~ /grep|mac-perf/) {
        printf "%s|%s|%s\n", $1, $2, cmd
      }
    }'
}

# Orphaned background processes (ppid=1, no controlling terminal)
scan_orphans() {
  ps -eo pid,ppid,tty,command 2>/dev/null | awk '
    NR==1{next}
    {
      pid=$1+0; ppid=$2+0; tty=$3
      cmd=""; for(i=4;i<=NF;i++) cmd=cmd " "$i; cmd=substr(cmd,2)
      if (ppid==1 && cmd ~ /git fsmonitor--daemon/) printf "%d|orphan-fsmonitor|%s\n", pid, cmd
      if (ppid==1 && cmd ~ /caffeinate/)             printf "%d|orphan-caffeinate/|%s\n", pid, cmd
    }'
}

# Duplicate background workers (keep newest 2 per pattern)
scan_duplicates() {
  for pattern in "mcp-server" "context7-mcp" "chrome-devtools-mcp"; do
    pids=$(pgrep -af "$pattern" 2>/dev/null | awk '!/grep|mac-perf/ {print $1}' | tail -r | tail -n +3)
    for p in $pids; do echo "$p|duplicate|$pattern"; done
  done
}

# Caches: name|path|size_mb (only if size > threshold MB)
scan_caches() {
  local caches=(
    "chrome-cache|$HOME/Library/Caches/Google/Chrome|50"
    "chrome-sw|$HOME/Library/Application Support/Google/Chrome/Default/Service Worker|50"
    "npm-cache|$HOME/.npm/_cacache|100"
    "bun-cache|$HOME/.bun/install/cache|200"
    "user-cache|$HOME/.cache|100"
    "pip-cache|$HOME/Library/Caches/pip|50"
    "yarn-cache|$HOME/Library/Caches/Yarn|50"
    "xcode-derived|$HOME/Library/Developer/Xcode/DerivedData|200"
    "logs|$HOME/Library/Logs|50"
    "quicklook|$HOME/Library/Caches/com.apple.QuickLook.thumbnailcache|50"
  )
  for entry in "${caches[@]}"; do
    IFS='|' read -r name path threshold <<< "$entry"
    [ ! -e "$path" ] && continue
    local size
    size=$(du -sm "$path" 2>/dev/null | awk '{print $1}')
    [ "${size:-0}" -ge "$threshold" ] && echo "$name|$path|$size"
  done
}

# ── REPORT MODE ────────────────────────────────────────────────────────────
do_report() {
  local avail swap_used total_swap up load total_procs node_procs chrome_procs
  avail=$(available_mb)
  swap_used=$(swap_used_mb)
  total_swap=$(swap_total_mb)
  up=$(uptime_days)
  load=$(load_avg)
  total_procs=$(ps -ax | wc -l | tr -d ' ')
  node_procs=$(pgrep -f node 2>/dev/null | wc -l | tr -d ' ')
  chrome_procs=$(pgrep -fi chrome 2>/dev/null | wc -l | tr -d ' ')

  say ""
  say "╔══════════════════════════════════════════════════════════╗"
  say "║              MAC-PERF REPORT                              ║"
  say "╚══════════════════════════════════════════════════════════╝"
  say ""
  say "▸ System"
  say "    Uptime:     ${up} days"
  say "    Load avg:   ${load}"
  say "    Avail RAM:  $(human_mb "$avail")"
  say "    Swap used:  $(human_mb "$swap_used") / $(human_mb "$total_swap")"
  say "    Procs:      ${total_procs} (node:${node_procs}, chrome:${chrome_procs})"
  say ""

  say "▸ Stale dev servers (>2h elapsed)"
  local stale; stale=$(scan_stale_dev_servers)
  if [ -z "$stale" ]; then say "    (none)"; else
    echo "$stale" | while IFS='|' read -r pid mins cmd; do
      say "    PID $pid  ${mins}m  $(echo "$cmd" | cut -c1-70)"
    done
  fi
  say ""

  say "▸ Hot dev servers (>50% CPU)"
  local hot; hot=$(scan_hot_dev_servers)
  if [ -z "$hot" ]; then say "    (none)"; else
    echo "$hot" | while IFS='|' read -r pid cpu cmd; do
      say "    PID $pid  ${cpu}% CPU  $(echo "$cmd" | cut -c1-70)"
    done
  fi
  say ""

  say "▸ Orphans / duplicate workers"
  local orphans; orphans=$(scan_orphans; scan_duplicates)
  if [ -z "$orphans" ]; then say "    (none)"; else
    echo "$orphans" | while IFS='|' read -r pid reason cmd; do
      say "    PID $pid  $reason  $(echo "$cmd" | cut -c1-60)"
    done
  fi
  say ""

  say "▸ Cleanable caches"
  local caches; caches=$(scan_caches)
  if [ -z "$caches" ]; then say "    (none above threshold)"; else
    echo "$caches" | while IFS='|' read -r name path size; do
      say "    $(printf '%-15s %s' "$name" "$(human_mb "$size")")"
    done
    local total_mb
    total_mb=$(echo "$caches" | awk -F'|' '{s+=$3} END{print s}')
    say "    ───────────────────────"
    say "    $(printf '%-15s %s' 'TOTAL' "$(human_mb "$total_mb")")"
  fi
  say ""

  say "▸ Recommendations"
  [ "$up" -gt 14 ] && say "    ⚠  Reboot recommended (uptime ${up}d, swap accumulates)"
  if [ -n "$total_swap" ] && [ "$total_swap" -gt 0 ] 2>/dev/null; then
    local swap_pct=$(( swap_used * 100 / total_swap ))
    [ "$swap_pct" -gt 80 ] && say "    ⚠  Swap thrashing (${swap_pct}%)"
  fi
  [ "$total_procs" -gt 500 ] && say "    ⚠  Process count high (${total_procs})"
  say ""
  say "Run:  mac-perf clean       (safe — kill stales, clear caches)"
  say "      mac-perf aggressive  (also kill hot dev servers)"
  say ""
}

# ── KILL HELPERS ───────────────────────────────────────────────────────────
kill_pid() {
  local pid=$1 reason=$2
  kill "$pid" 2>/dev/null && {
    say "    killed PID $pid ($reason)"
    log "killed $pid ($reason)"
    sleep 0.3
    kill -0 "$pid" 2>/dev/null && kill -9 "$pid" 2>/dev/null
    return 0
  }
  return 1
}

clear_path() {
  local path=$1
  [ ! -e "$path" ] && return
  local size
  size=$(du -sm "$path" 2>/dev/null | awk '{print $1}')
  rm -rf "${path:?}"/* 2>/dev/null
  say "    cleared $path ($(human_mb "${size:-0}"))"
  log "cleared $path ($size MB)"
}

confirm() {
  [ "$YES" = 1 ] && return 0
  printf "%s [y/N] " "$1" >&2
  read -r ans </dev/tty
  [ "$ans" = "y" ] || [ "$ans" = "Y" ]
}

# ── CLEAN MODE ─────────────────────────────────────────────────────────────
do_clean() {
  local aggressive=${1:-0}
  local avail_before swap_before
  avail_before=$(available_mb)
  swap_before=$(swap_used_mb)

  say ""
  say "▸ Killing stale dev servers (>2h idle)..."
  local stale; stale=$(scan_stale_dev_servers)
  if [ -n "$stale" ]; then
    if confirm "  Kill $(echo "$stale" | wc -l | tr -d ' ') stale dev servers?"; then
      echo "$stale" | while IFS='|' read -r pid mins cmd; do
        kill_pid "$pid" "stale-${mins}m"
      done
    fi
  else say "    (none)"; fi

  say ""
  say "▸ Killing orphans + duplicate workers..."
  (scan_orphans; scan_duplicates) | while IFS='|' read -r pid reason cmd; do
    kill_pid "$pid" "$reason"
  done

  if [ "$aggressive" = 1 ]; then
    say ""
    say "▸ [AGGRESSIVE] Killing hot dev servers (>50% CPU)..."
    local hot; hot=$(scan_hot_dev_servers)
    if [ -n "$hot" ]; then
      if confirm "  Kill $(echo "$hot" | wc -l | tr -d ' ') hot dev servers?"; then
        echo "$hot" | while IFS='|' read -r pid cpu cmd; do
          kill_pid "$pid" "hot-${cpu}%"
        done
      fi
    else say "    (none)"; fi
  fi

  say ""
  say "▸ Clearing caches..."
  local caches; caches=$(scan_caches)
  if [ -n "$caches" ]; then
    local total
    total=$(echo "$caches" | awk -F'|' '{s+=$3} END{print s}')
    if confirm "  Clear caches (~$(human_mb "$total"))?"; then
      echo "$caches" | while IFS='|' read -r name path size; do
        # Skip chrome-sw if Chrome is running and not in aggressive mode
        if [ "$name" = "chrome-sw" ] && [ "$aggressive" = 0 ] && pgrep -fi "Google Chrome" >/dev/null; then
          say "    skipped $name (Chrome running, use aggressive)"; continue
        fi
        clear_path "$path"
      done
    fi
  else say "    (none above threshold)"; fi

  # macOS purge (frees inactive memory) — requires sudo
  if [ "$aggressive" = 1 ]; then
    say ""
    say "▸ Running sudo purge..."
    sudo -n purge 2>/dev/null && say "    purged" || say "    (skipped — needs sudo NOPASSWD for /usr/sbin/purge)"
  fi

  local avail_after swap_after
  avail_after=$(available_mb)
  swap_after=$(swap_used_mb)
  say ""
  say "╔══════════════════════════════════════════════════════════╗"
  say "║  RESULT                                                   ║"
  say "╚══════════════════════════════════════════════════════════╝"
  say "  RAM avail:  $(human_mb "$avail_before") → $(human_mb "$avail_after")  (Δ $(human_mb "$((avail_after - avail_before))"))"
  say "  Swap used:  $(human_mb "$swap_before") → $(human_mb "$swap_after")"
  say ""

  local up; up=$(uptime_days)
  [ "$up" -gt 14 ] && say "  ⚠  Reboot still recommended (uptime ${up}d) — swap won't fully release until reboot"
  say ""
  log "done mode=$([ "$aggressive" = 1 ] && echo aggressive || echo clean) avail=${avail_before}→${avail_after} swap=${swap_before}→${swap_after}"
}

# ── DISPATCH ───────────────────────────────────────────────────────────────
case "$MODE" in
  report|"")    do_report ;;
  clean)        do_clean 0 ;;
  aggressive)   do_clean 1 ;;
  -h|--help)
    sed -n '2,19p' "$0" | sed 's/^# \{0,1\}//'
    exit 0 ;;
  *)            echo "Usage: mac-perf [report|clean|aggressive] [--yes] [--quiet]" >&2; exit 1 ;;
esac