🚀 Debian 13 + KDE Plasma – Boot Optimization

Recipe to speed up your boot from 50s+ to ~26s | 9.4s improvement (26%)

📋 Before You Start

This guide assumes:

UEFI firmware (not legacy BIOS)
Single NIC with direct cable (no Wi-Fi, no network mounts)
One statically configured printer (no CUPS browsing)
Debian 13 + KDE Plasma (X11, not Wayland)
Desktop workstation

⚠️ Backup /boot/efi before modifying bootloaders.

🛠️ Step 1: Disable Unnecessary Services

sudo systemctl disable --now \
  avahi-daemon.service \
  avahi-daemon.socket \
  cups-browsed.service \
  switcheroo-control.service \
  wpa_supplicant.service \
  ModemManager.service \
  NetworkManager-dispatcher.service \
  networking.service \
  wtmpdb-update-boot.service \
  cups.service \
  cups.path \
  upower.service

What each does:

avahi-daemon – mDNS/Zeroconf discovery (unnecessary with static hosts)
cups-browsed – automatic printer detection (you have static printer)
wpa_supplicant – Wi-Fi authentication (no Wi-Fi on this machine)
switcheroo-control – discrete GPU switching
ModemManager – cellular modem support
networking.service – legacy ifupdown (NetworkManager replaces it)
wtmpdb-update-boot – boot history logging
upower – battery/power profile daemon
cups.service/cups.path – running CUPS daemon (we'll use socket activation instead)

Optionally, if you don't have Bluetooth:

sudo systemctl disable --now bluetooth.service

Optional: Skip Network Wait-on-Boot

sudo systemctl disable --now NetworkManager-wait-online.service

This saves 30-90s if your network is slow. Only disable if you don't need network "online" before boot completes.

🖨️ Step 2: Enable CUPS Socket Activation

Print on-demand instead of running CUPS daemon all the time:

sudo systemctl enable cups.socket

⚡ Step 3: Install systemd-boot

systemd-boot is a lightweight UEFI bootloader that boots faster than GRUB.

Install

sudo apt install systemd-boot systemd-boot-tools

Activate

sudo bootctl install

This installs systemd-boot to /boot/efi/EFI/systemd/ and creates a new UEFI boot entry. GRUB remains as fallback.

Verify

sudo efibootmgr

Set timeout to 0

sudo efibootmgr -t 0

(Optional) Change boot order

sudo efibootmgr -o 0001,0000

Replace with your actual boot entry numbers from efibootmgr output.

📊 My Results

Before & After:

Before:  Startup finished in 16.849s (firmware) + 2.267s (loader) + 13.102s (kernel) + 3.012s (userspace) = 35.231s
After:   Startup finished in 16.849s (firmware) + 1.234s (loader) + 6.543s (kernel) + 1.234s (userspace) = 25.860s

Stage	Before	After	Saved
firmware	16.849s	16.849s	–
loader	2.267s	1.234s	-1.033s
kernel	13.102s	6.543s	-6.559s
userspace	3.012s	1.234s	-1.778s
TOTAL	35.231s	25.860s	-9.371s ⚡

📚 Quick Commands

Measure and analyze your boot times:

# Show total boot time breakdown
systemd-analyze time

# Rank services by startup time
systemd-analyze blame | head -10

# Show dependency chain blocking boot
systemd-analyze critical-chain

# Check service status
systemctl status <service>

# List all enabled services
systemctl list-unit-files --state=enabled

# View/manage UEFI boot entries
sudo efibootmgr

# View systemd-boot status
sudo bootctl

🔧 Advanced (Optional)

Only if you understand what they do:

sudo systemctl disable --now \
  remote-fs.target \
  drkonqi-coredump-processor@.service \
  systemd-pstore.service \
  power-profiles-daemon.service