Linux Kernel Management

Linux Kernel Management Guide

Complete beginner-friendly guide to managing kernels on Linux, covering Arch Linux, CachyOS, and other distributions including installation, removal, switching, kernel parameters, and custom kernels.

---

Table of Contents

1. Understanding Kernels
2. Available Kernels
3. Installing Kernels
4. Removing Kernels
5. Switching Kernels
6. Kernel Parameters
7. CachyOS-Specific Kernels
8. Custom Kernels
9. Troubleshooting

---

Understanding Kernels

What is a Kernel?

Kernel is the core of the operating system.

What it does:

• Manages hardware: Controls hardware devices
• Manages memory: Handles RAM and memory
• Manages processes: Controls running programs
• System interface: Interface between hardware and software

Why different kernels:

• Different schedulers: BORE, EEVDF, CFS, etc.
• Different features: RT, LTS, etc.
• Different optimizations: Performance, stability

Kernel Versions

Version format:

6.6.0-arch1
│ │ │ └─── Build number
│ │ └───── Patch version
│ └─────── Minor version
└───────── Major version

---

Available Kernels

Official Kernels (Arch)

Available in repositories:

• linux: Latest stable kernel
• linux-lts: Long-term support kernel
• linux-hardened: Security-hardened kernel
• linux-zen: Performance-optimized kernel

Check Installed Kernels

List installed kernels:

# List installed kernels
pacman -Q | grep linux

# Check running kernel
uname -r

---

Installing Kernels

Install Stable Kernel

Install latest kernel:

# Arch
sudo pacman -S linux linux-headers

# For firmware
sudo pacman -S linux-firmware

Install LTS Kernel

Install LTS kernel:

# Arch
sudo pacman -S linux-lts linux-lts-headers

Install Zen Kernel

Install Zen kernel:

# Arch
sudo pacman -S linux-zen linux-zen-headers

---

Removing Kernels

Remove Kernel

Remove kernel:

# Remove kernel
sudo pacman -R linux

# Remove with headers
sudo pacman -R linux linux-headers

Clean Old Kernels

Remove old kernels:

# List kernels
pacman -Q | grep linux

# Remove old kernels (keep current)
sudo pacman -R linux-old-version

---

Switching Kernels

Switch at Boot

Select kernel at boot:

1. Boot menu (GRUB/systemd-boot)
2. Select kernel from menu
3. Boot

Set Default Kernel

Edit bootloader:

# Edit GRUB
sudo vim /etc/default/grub

# Regenerate
sudo grub-mkconfig -o /boot/grub/grub.cfg

---

Kernel Parameters

Edit Kernel Parameters

Edit GRUB:

# Edit GRUB
sudo vim /etc/default/grub

Add parameters:

GRUB_CMDLINE_LINUX_DEFAULT="quiet mitigations=off"

Regenerate:

sudo grub-mkconfig -o /boot/grub/grub.cfg

---

CachyOS-Specific Kernels

CachyOS Kernels

linux-cachyos:

• Scheduler: BORE (default)
• Best for: Desktop, gaming
• Features: Performance optimized

linux-cachyos-eevdf:

• Scheduler: EEVDF
• Best for: General use, servers
• Features: Modern fair scheduler

linux-cachyos-sched-ext:

• Scheduler: sched-ext (extensible)
• Best for: Advanced users
• Features: Custom schedulers

linux-cachyos-rt:

• Type: Real-time kernel
• Best for: Real-time applications
• Features: Low latency

linux-cachyos-lts:

• Type: Long-term support
• Best for: Stability
• Features: Long-term updates

Install CachyOS Kernels

Install linux-cachyos:

sudo pacman -S linux-cachyos linux-cachyos-headers

Install other kernels:

sudo pacman -S linux-cachyos-eevdf linux-cachyos-eevdf-headers

See CachyOS Kernel Management for detailed CachyOS kernel guide.

---

Custom Kernels

Compile Custom Kernel

See Kernel Compilation for detailed guide.

---

Troubleshooting

Kernel Not Booting

Boot from previous kernel:

1. Boot menu
2. Select previous kernel
3. Boot

Kernel Modules Not Loading

Check modules:

# Check loaded modules
lsmod

# Load module
sudo modprobe module-name

---

Summary

This guide covered kernel management for Arch Linux, CachyOS, and other distributions, including installation, removal, switching, kernel parameters, and CachyOS-specific kernels.

---

Next Steps

• Bootloader Configuration - Bootloader setup
• CachyOS Kernel Management - CachyOS kernels
• Kernel Compilation - Custom kernels
• ArchWiki Kernel: https://wiki.archlinux.org/title/Kernel

---

This guide covers Arch Linux, CachyOS, and other Linux distributions. CachyOS-specific kernels are highlighted where applicable.