Use sudo nice for high priority without requiring root shell

Instead of requiring the user to run the whole command as root (which
loses PATH and can't find node/pnpm), use 'sudo nice -n -20 node ...'
so only the nice call is elevated. Activates automatically when
passwordless sudo is available.

Co-Authored-By: Claude Opus 4.6 (1M context) <[email protected]>

Author: NullVoxPopuli

scripts/bench-compare.mjs

@@ -119,12 +119,19 @@ try {
     console.error('📌  CPU pinning enabled (taskset -c 0)');
   }
 
-  if (HAS_NICE && process.getuid?.() === 0) {
+  const IS_ROOT = process.getuid?.() === 0;
+  const HAS_SUDO = IS_LINUX && spawnSync('sudo', ['-n', 'true'], { stdio: 'pipe' }).status === 0;
+
+  if (HAS_NICE && IS_ROOT) {
     fullArgs = ['-n', '-20', cmd, ...fullArgs];
     cmd = 'nice';
     console.error('⚡  High priority enabled (nice -n -20)');
+  } else if (HAS_NICE && HAS_SUDO) {
+    fullArgs = ['nice', '-n', '-20', cmd, ...fullArgs];
+    cmd = 'sudo';
+    console.error('⚡  High priority enabled (sudo nice -n -20)');
   } else if (HAS_NICE) {
-    console.error('💡  Run with sudo for high scheduling priority (nice -n -20)');
+    console.error('💡  High priority unavailable (needs passwordless sudo)');
   }
 
   console.error('');

scripts/run-bench.sh

@@ -17,13 +17,16 @@ if command -v taskset &>/dev/null; then
   echo "📌  CPU pinning enabled (taskset -c 0)" >&2
 fi
 
-# High scheduling priority (best-effort, needs root for negative values)
+# High scheduling priority (best-effort, negative nice needs root)
 if command -v nice &>/dev/null; then
   if [ "$(id -u)" = "0" ]; then
     CMD=(nice -n -20 "${CMD[@]}")
     echo "⚡  High priority enabled (nice -n -20)" >&2
+  elif command -v sudo &>/dev/null && sudo -n true 2>/dev/null; then
+    CMD=(sudo nice -n -20 "${CMD[@]}")
+    echo "⚡  High priority enabled (sudo nice -n -20)" >&2
   else
-    echo "💡  Run with sudo for high scheduling priority (nice -n -20)" >&2
+    echo "💡  High priority unavailable (needs passwordless sudo)" >&2
   fi
 fi