PsyCachy Kernel

This repository contains the releases of the linux-psycachy and linux-psycachy-lts kernels, and the script for building it. The script may automate the process of configuring and optimizing the kernel build according to your hardware and preferences.

What's this about?

PsyCachy is a kernel with improved settings for compatibility and stability across Debian/Ubuntu Linux distributions derived from linux-cachyos.

Differences to linux-cachyos

• Doesn't include processor architecture-specific optimizations, as they bring too small gains to justify the time compiling them or the confusion caused to newcomers by multiple kernel versions on release - you can include those by building the kernel yourself running cachyos-deb.sh with -b option if you wish.
• Doesn't include handheld console drivers, as there isn't much of a point on doing it for Debian/Ubuntu.
• OS/-o2 optimization instead of -o3, which caused quite a few problems with Debian/Ubuntu packages.

Recommended usage

Install the kernel image of your choice from Releases or through LinuxToys.

Choosing your kernel

• linux-psycachy is more up-to-date on features, and follows a predictable release schedule of about every two months, enough time for each kernel release to mature enough to be unproblematic.
• linux-psycachy-lts offers a more stable and secure choice, following upstream releases of the latest version marked as longterm from The Linux Kernel Archives.

Manual installation

• Download all three .deb packages
• Open terminal in the same directory of the packages
• sudo dpkg -i linux-image-psycachy_6.14.11-1_amd64.deb linux-headers-psycachy_6.14.11-1_amd64.deb linux-libc-dev_6.14.11-1_amd64.deb
• To install CachyOS SystemD configuration files as well to maximize effectiveness, download and run cachyconfs.sh available from Releases.

Secure Boot

You can make the kernel compatible with Secure Boot by signing it using create-key.sh available from Releases. Remember to store the password you set when the keypair is created carefully.

Building

Prerequisites

Before running the script, ensure you have the following prerequisites installed:

• gcc: The GNU Compiler Collection is required for detecting the CPU architecture.
• clang: Required for compiling the kernel.
• whiptail: For displaying dialog boxes in the script.
• curl: For fetching the latest kernel version.
• rustc: For building newer, Rust-based kernel modules.
• debhelper: For packaging.

You can install these dependencies using your distribution's package manager, or have cachyos-deb.sh install them for you.

Features

The script offers a variety of configuration options:

• Auto-detection of CPU architecture for optimization.
• Selection of CachyOS specific optimizations.
• Configuration of CPU scheduler, LLVM LTO, tick rate, and more.
• Support for various kernel configurations such as NUMA, NR_CPUS, Hugepages, and LRU.
• Application of O3 optimization and performance governor settings.

Usage

To use the script, follow these steps:

1. Clone the repository to your local machine.
2. Make the script executable with chmod +x cachyos-deb.sh.
3. Run the script with ./cachyos-deb.sh.
4. Follow the on-screen prompts to select your desired kernel version and configurations, for:
   • Choose the kernel version.
   • Enable or disable CachyOS optimizations.
   • Configure the CPU scheduler, LLVM LTO, tick rate, NR_CPUS, Hugepages, LRU, and other system optimizations.
   • Select the preempt type and tick type for further system tuning; or
5. Install with optimized defaults and my custom 'stable' branch, which is updated roughly every two months, with ./cachyos-deb.sh -s. This has been thoroughly tested on Debian Testing and Ubuntu (with Gnome, the standard Canonical flavour), but should work elsewhere without complications.

Launch options

• -b: builds a psycachy-variant kernel with optimizations specific to your CPU MARCH.
• -g: builds the same psycachy generic image found in Releases. Meant just to generate those images.
• -l: builds the same psycachy-lts generic image found in Releases. Meant just to generate those images.
• -c: builds a linux-cachyos kernel with latest spec and settings. This is not guaranteed to work, as it uses CachyOS's defaults.

Advanced Configurations

The script includes advanced configuration options for users who want to fine-tune their kernel:

• CachyOS Configuration: Enable all optimizations from CachyOS. A kernel with this option enabled is not guaranteed to work.
• CPU Scheduler: Choose between different schedulers like Cachy, PDS, or none.
• LLVM LTO: Select between Thin and Full LTO for better optimization.
• Tick Rate: Configure the kernel tick rate according to your system's needs.
• NR_CPUS: Set the maximum number of CPUs/cores the kernel will support.
• Hugepages: Enable or disable Hugepages support.
• LRU: Configure the Least Recently Used memory management mechanism.
• O3 Optimization: Apply O3 optimization for performance improvement.
• Performance Governor: Set the CPU frequency scaling governor to performance.
• Modprobed.db: will use the database built from modprobed.db to only build drivers specific to your machine. WARNING: use the default kernel with modprobed.db up and running for at least a week before building with this option to make sure all drivers you need are on the database, and always keep a default (or psycachy generic package) kernel as a backup!

Contributing

Contributions are welcome! If you have suggestions for improving the script or adding new features, please open an issue or submit a pull request.

License

This project is licensed under the MIT License - see the LICENSE file for details.