noise-diagnosis

---
name: noise-diagnosis
description: Use when the user reports laptop noise, fan spinning, heat, or high temperatures. Diagnoses which processes are consuming excessive CPU or GPU resources and offers to kill them.
---

# Noise Diagnosis

Diagnose and resolve laptop fan noise by identifying runaway processes.

## Steps

### 1. Identify CPU hogs

```bash
top -b -n1 | head -20
```

Look for processes using >50% CPU. Note PIDs and command names.

### 2. Check GPU

```bash
nvidia-smi
```

Look for unexpected GPU utilization or high power draw.

### 3. Identify what the processes are

For each high-CPU process, check its working directory and full command:

```bash
ls -la /proc/<PID>/cwd
cat /proc/<PID>/cmdline | tr '\0' ' '
```

### 4. Report findings

Tell the user:
- What processes are consuming resources
- What they are (MCP servers, dev servers, builds, etc.)
- How long they've been running
- Whether they look like orphans from old sessions

### 5. Kill on confirmation

Only kill after user confirms. Try SIGTERM first:

```bash
kill <PIDs>
```

If processes survive (check with `top` or `ps`), escalate to SIGKILL:

```bash
kill -9 <PIDs>
```

### 6. Verify

Confirm processes are dead and CPU has dropped. Note that fans may take 30-60 seconds to spin down as the heatsink cools.

## Common culprits

- Orphaned MCP servers (`bun server.ts`) from old Claude Code sessions
- Zombie dev servers (webpack, vite, next)
- Stuck build processes
- Browser renderer processes in infinite loops