CachyOS

CachyOS provides enhanced kernels that offer improved performance and other benefits.

• General Information about kernels
  • linux-cachyos
  • Features
• CachyOS repositories
  • How to add CachyOS repositories
  • Check CPU compatibility
  • Uninstalling CachyOS repositories
  • Install SCX schedulers - only for linux-cachyos-sched-ext
• Other GNU/Linux distributions
  • Gentoo
  • Fedora
  • NixOS
• Support

General Information about kernels

Scheduler Support

We have provided all these CPU schedulers because each scheduler performs differently depending on usage. We recommend testing each one to determine which best suits your specific requirements.

• (BORE) Burst-Oriented Response Enhancer Scheduler by firelzrd linux-cachyos / linux-cachyos-bore

• (EEVDF) Earliest Eligible Virtual Deadline - linux-cachyos-eevdf

• (BMQ) BitMap queue CPU Scheduler Scheduler by Alfred Chen - linux-cachyos-bmq

[!NOTE] The CachyOS repositories provide prebuilt kernels in three different march versions: x86-64, x86-64-v3,x86-64-v4 and znver4. The default linux-cachyos kernel is compiled with Clang, Thin LTO and uses our AutoFDO profile. For this kernel there is a linux-cachyos-gcc variant available.

Features

🛠️ Advanced building & compiling

• Very customizable PKGBUILD with many features and improvements.
• Auto detection of CPU architecture and setting the appropriate compiler flags.
• Support for building with GCC or Clang.
• Choose between 300Hz, 500Hz, 600 Hz ,750Hz and 1000Hz. Defaults to 1000Hz
• Kernel Control Flow Integrity (kCFI) selectable when using LLVM
• Support for generating and using AutoFDO profiles, which is a PGO-like optimization. See more: https://cachyos.org/blog/2411-kernel-autofdo/

🧮 CPU enhancements

• 3 different scheduler are supported: BORE, EEVDF and BMQ scheduler
• AMD P-State Preferred Core / amd-pstate enhancements and fixes from linux-next.
• AMD 3D V-Cache optimizer driver
• Support for RT kernel builds with BORE
• Cachy Sauce CONFIG_CACHY, enables various tweaks for the scheduler and other settings
• Includes patches to improve performance of CRC32 and AES128 crypto.

📑 Filesystem & memory

• ZFS Filesystem support and pre-built modules for our kernels in the repository
• Support for building NVIDIA modules with some patches. Ready modules for binary kernel builds can be found in the repository.
• Latest & improved ZSTD 1.5.6 patch-set
• KSM patch for proper working of uksmd daemon from pf
• Memory management tweaks from zen-kernel (MGLRU, Compaction, Watermark)

⤵️ Other features

• Cherry-picked Clear Linux patches
• Back-ported patches from linux-next
• ACS Override support
• AMDGPU: Allow override of min_powercap with amdgpu_ignore_min_pcap
• Steam Deck Patches included - Audio, HW Quirks, HID
• Rog Ally patches included
• v4l2loopback modules as default included
• HDR support enabled
• Various GCC Optimization flags applied (-fivopts -fmodulo-sched)
• NTSync module support (NTSYNC=m)
• T2 Macbook support as default included

Explaination of the kernel variants

CachyOS repositories

The repositories contain both Arch Linux and CachyOS packages, which have been re-built with flags optimized for performance, stability, and security.

• znver4 - Dedicated Zen4 optimized repository used for Zen 4 and Zen 5 CPUs
• x86-64-v4 - all Arch Linux packages with enhanced compilation flags
• x86-64-v3 - all Arch Linux packages with enhanced compilation flags
• x86-64 - currently only kernel packages

How to add CachyOS repositories

Option 1: Automated Installation of CachyOS repositories

We've made it easy for you! Simply run the following commands to use our helper script that does all the work for you. 😉

Run the following commands:

1. Get archive with script

curl -O https://mirror.cachyos.org/cachyos-repo.tar.xz

2. Extract and enter into the archive

tar xvf cachyos-repo.tar.xz && cd cachyos-repo

3. Run script with sudo

sudo ./cachyos-repo.sh

Behaviour of script

1. Script will auto-detect CPU architecture, if CPU has x86-64-v4 or x86-64-v3 support, script will automatically use the repositories, which are optimized with this flag and some other flags.

2. Script will backup your old pacman.conf.

For more information, check out our GitHub or join our Discord community.

Option 2: Manual Installation

1. Add CachyOS signing keys

sudo pacman-key --recv-keys F3B607488DB35A47 --keyserver keyserver.ubuntu.com
sudo pacman-key --lsign-key F3B607488DB35A47

2. Install required packages

Caution

Installing the CachyOS Pacman, will install a forked pacman with features added from CachyOS, like "INSTALLED_FROM" and an automatic architecture check.

Pacman 6.1 added a feature validation feature, which could lead when using the Arch Linux pacman into warnings. We are working with Arch Linux to provide a proper compatibility again.

If you want to avoid this, don't add the "cachyos" repository, which contains the customized pacman. All other repositories like cachyos-v3, cachyos-v4, cachyos-extra/core-v3/4 are fine to add.

sudo pacman -U 'https://mirror.cachyos.org/repo/x86_64/cachyos/cachyos-keyring-20240331-1-any.pkg.tar.zst' \
    'https://mirror.cachyos.org/repo/x86_64/cachyos/cachyos-mirrorlist-18-1-any.pkg.tar.zst' \
    'https://mirror.cachyos.org/repo/x86_64/cachyos/cachyos-v3-mirrorlist-18-1-any.pkg.tar.zst' \
    'https://mirror.cachyos.org/repo/x86_64/cachyos/cachyos-v4-mirrorlist-6-1-any.pkg.tar.zst' \
    'https://mirror.cachyos.org/repo/x86_64/cachyos/pacman-7.0.0.r6.gc685ae6-2-x86_64.pkg.tar.zst'

If you want to go back to the Arch Linux repositories and had our version of pacman installed, you will need to run the following command after the rollback to avoid getting %INSTALLED_DB% warnings:

sudo find /var/lib/pacman/local/ -type f -name "desc" -exec sed -i '/^%INSTALLED_DB%$/,+2d' {} \;

Check CPU compatibility

If you want to add our repositories manually, you must check the compatibility of the CPU with cachyos repositories.

Note

If you are using the script above to add CachyOS repositories, you can skip the check.

1. Check support by running the following the command

/lib/ld-linux-x86-64.so.2 --help | grep supported

2. Understanding of command output

Pay attention to the following text with brackets. (supported, searched)

• If you see x86-64-v4 (supported, searched), that means the CPU is compatible and can use x86-64-v4 instruction set.

• If you see x86-64-v4, that means the CPU is incompatible and can't use x86-64-v4 instruction set.

Example of CPU compatible with x86-64-v4 instruction set

> /lib/ld-linux-x86-64.so.2 --help | grep supported
  x86-64-v4 (supported, searched)
  x86-64-v3 (supported, searched)
  x86-64-v2 (supported, searched)

3. Adding cachyos repositories

You need to edit pacman.conf and add repositories.

sudo nano /etc/pacman.conf

if your CPU supports x86-64, then add only [cachyos] repositories

# cachyos repos
[cachyos]
Include = /etc/pacman.d/cachyos-mirrorlist

if your CPU supports x86-64-v3, then add [cachyos-v3],[cachyos-core-v3],[cachyos-extra-v3] and [cachyos]

# cachyos repos
## Only add if your CPU does v3 architecture
[cachyos-v3]
Include = /etc/pacman.d/cachyos-v3-mirrorlist
[cachyos-core-v3]
Include = /etc/pacman.d/cachyos-v3-mirrorlist
[cachyos-extra-v3]
Include = /etc/pacman.d/cachyos-v3-mirrorlist
[cachyos]
Include = /etc/pacman.d/cachyos-mirrorlist

if your CPU supports x86-64-v4, then add [cachyos-v4], [cachyos-core-v4], [cachyos-extra-v4] and [cachyos]

# cachyos repos
## Only add if your CPU does support x86-64-v4 architecture
[cachyos-v4]
Include = /etc/pacman.d/cachyos-v4-mirrorlist
[cachyos-core-v4]
Include = /etc/pacman.d/cachyos-v4-mirrorlist
[cachyos-extra-v4]
Include = /etc/pacman.d/cachyos-v4-mirrorlist
[cachyos]
Include = /etc/pacman.d/cachyos-mirrorlist

Finally, update your system with CachyOS packages:

sudo pacman -Syu

Enjoy improved system speed with CachyOS packages!

Debug packages

This is handled via debuginfod. Just add following file to /etc/debuginfod/cachyos.urls

https://debuginfod.cachyos.org

Uninstalling CachyOS repositories

See Uninstalling Cachyos Repositories

SCX Schedulers

See sched-ext Tutorial

Warning

Using sched-ext schedulers is not available when using the linux-cachyos-bmq kernel.

Other GNU/Linux distributions

• Complete patch for simple patching on the kernel

• It is planned to implement into our kernel builder from cachyos buildsystem, which works also on other distributions.

Gentoo

Its a community maintained ebuild from a user, which can be used for a dynamic building right here

Or simply run:

eselect repository add CachyOS-kernels git https://github.com/Szowisz/CachyOS-kernels
emaint sync -r CachyOS-kernels

Fedora

Port of kernel linux-cachyos-bore, linux-cachyos-rt-bore, linux-cachyos-bore-lto and linux-cachyos-lts by bieszczaders

Visit the COPR page for installation instructions and the latest announcements.

NixOS

Nyx does provide a precompiled CachyOS Kernel and a bunch of other interesting packages. This repository is maintained by chaotic-aur Just follow this README

Support

Discord: https://discord.gg/cachyos-862292009423470592
Forum: https://discuss.cachyos.org
Telegram: https://t.me/+zCzPX4cAFjk1MTYy
Matrix: https://matrix.cachyos.org

Donations appreciated for maintaining repositories and build server. Thank you for your support!

PayPal: https://paypal.me/pttrr
Patreon: https://www.patreon.com/CachyOS
BTC: bc1qmwglfchlc335du6pcu6w64cexu7cck0mzhyw42
ETH: 0xc2dc77327F78A7B85Db3941Eb49e74F41E961649
LTC: LgGTwcEBcXqMgNT6XyyNWABMb7dZVtVg9w

Valueable Contributors

firelzrd for the BORE Scheduler
Arch Linux for the great linux operating system
And all other Kernel Developers and Supporters