---
id: 775506ce-ed06-4c36-95f3-73379855b44a
type: fix
title: "High CPU on Docker host from avahi-daemon and GNOME"
tags: [cpu, docker, avahi, gnome, gdm, performance, homelab, fix]
importance: 0.7
confidence: 0.8
created: "2025-12-20T04:36:05.718983+00:00"
updated: "2025-12-20T04:36:05.718983+00:00"
relations:
  - target: 62ee21e8-2b56-4d38-a73d-47e2724f08c6
    type: BUILDS_ON
    direction: incoming
    strength: 0.5
---

**Problem:** Docker host showing constant ~12% CPU usage from background services.

**Root Cause:**
1. avahi-daemon (mDNS) constantly processing Docker veth interface changes (67+ hours accumulated CPU)
2. gvfs-udisks2-volume-monitor (GNOME disk monitor) running unnecessarily on server
3. gdm and gnome-shell running on headless server

**Solution:**
```bash
# Disable avahi (including socket to prevent respawn)
sudo systemctl stop avahi-daemon.socket avahi-daemon
sudo systemctl disable avahi-daemon.socket avahi-daemon

# Disable GNOME desktop
sudo systemctl stop gdm
sudo systemctl disable gdm

# Kill lingering processes
sudo pkill -f gvfs-udisks2-volume-monitor
```

**Result:** ~12% CPU and 180MB RAM recovered.

**When to apply:** Any Docker host with desktop environment installed that doesn't need GUI access.