Using immutable Linux OpenSuSE Kalpa Desktop for Gaming

Changelog

If you have already another operating system installed then please make a backup of all your data to a separate medium or different computer/host before changing the operating system. Otherwise you may loose all of it without recovery.

Introduction

Linux for gaming is on the rise since the last years. There are multiple reasons for this:

• Wide support from latest modern hardware (including latest GPUs) to very old hardware - Making sure your investment provides value
• A wide range of platforms and operating systems can be emulated or run near-natively
• Often better performance and stability than on other operating systems
• Can run games that are not supported anymore on other operating systems
• Avoid licensing costs and unnecessary hardware upgrades

• They are minimal operating systems to run different workloads in a highly isolated manner without impacting each other: This is ideal to run different games with different requirements. This is based ont he concept of container technologies.
• Updates to the host operating systems are transcational. If your upgrade does not work (e.g. does not boot, errors etc.) then you simply switch to a previous working state of the system in an instant (select from the boot menu). This is based on technologies such as Btrfs.
• Designed for a high update frequency so you can have the latest software and driver releases in an instant

Installation of Kalpa Desktop

The installation is rather simple and you can follow the instructions.
There is nothing specifically to consider here all hardware is detected and configured automatically.
You may want to configure the following aspects during installation (you can also do it afterwards, but it is simpler during installation):

• Encrypt your hard drive: This you should do, because otherwise people can recover your data once you sell your hardware or it breaks. The reason is that with modern hard drives it is difficult to delete data fully.
• Configure the NTP time servers (all four of them) of the German National Metrology Institute (Physikalisch-Technische Bundesanstalt, PTB). They are based on very precise Atomic Clocks

Configure for Gaming

Kalpa Desktop uses Security-Enhanced Linux (SElinux). This protects your computer from badly written software and can avoid some (but not all) attacks of malicous software (you should in all cases have always an independent backup and test it regularly).

As Windows does not offer sophisticated protection mechanisms, also Windows application and Windows games do not take them into account. Most of them will require to have the OpenSuSE package for enabling selinux policies for gaming.
You can simply install them as follows:
sudo transactional-update pkg in -y selinux-policy-targeted-gaming
Note: It is acceptable for a Gaming PC to install this policy, if you need to emulate insecure operating systems, such as Windows. However, use it only if needed for your Gaming PC and do not use it for non-gaming PCs.

You can find more background information in Annex: SElinux and Gaming

Configure peripherals

USB Peripherals

Virtually all modern and older USB peripherals, such as Gamepads, Joysticks, Yokes, Pedals, etc., run out of the box on Linux. Thus, you just simply connect them and that is all.

However, since we said in the beginning we should run games as normal users and not root, you need to allow user access.

This is done by providing udev rules in files (see for some peripheral in the annex).

How can you come up with an udev rule?
First you need to plug your peripheral(s) into the USB port of your Gaming PC.
Then you check via the following command some information of your device
lsusb
This will return a list of all usb devices

We highlighted here two values the vendor id (which is the first value), 294b, and the product id (which is the second value), 1903.

You now need to create (as root) a file in /etc/udev/rules.d/ with the filename NN-name.rules, where NN stands for a digit priority number (low number = higher priority) and a name of the rule. Example: 65-honeycomb.rules.
This file has the following content to enable user access to the peripheral we highlighted in the screenshot:
SUBSYSTEMS=="usb", ATTRS{idVendor}=="294b", ATTRS{idProduct}=="1903", TAG+="uaccess", ENV{ID_INPUT_JOYSTICK}="1"
You can easily see where to put the vendor id and the product id in the file. Find here more rules on the udev rules syntax.

Once you have defined the rules you need to load them once by using the following command
sudo udevadm control --reload-rules && sudo udevadm trigger

Bluetooth

You connect bluetooth devices like you would do on any other operating system. You need to put them in pairing mode and then you can click on the Desktop on the Bluetooth symbol and connect them.

Similarly to USB, virtually all modern and old Bluetooth devices are supported, including popular Console Gamepads, such as the PS5 Controller.
Some peripherals you can switch off using a button on the peripheral itself. Others are switched off by disconnecting the Bluetooth connection using the Bluetooth configuration dialog mentioned before (e.g. PS5 Controller).

Game Launcher: Heroic

Unfortunately, for the Heroic Game Launcher for some games you need to enable peripherals, such as Gamepads, specifically per game, if they do not work in this game. However, this is simple.
Go to the settings of the game.

Add a new environment variable with the following content:
Variable Name: PROTON_PREFER_SDL
Value: 1
See also the following screenshot:

Installing game distribution software

While you can in some cases download games directly from a website or you can fetch the Flatpak (see next section), the most common way for native and non-native Linux game are launcher. These launchers also automatically configure and run everything to run non-native Linux games, such as Windows ones. They also fetch automatically the games that you bought and make them available for installation/star.
You can install the following popular launcher:

• Lutris - Open Gaming Platform
- Supports various game launchers, such as Ubisoft Connect, Gog.com, Steam, Epic Games, Electronic Arts, Dolphin, Humble Bundle
• Heroic Games Launcher - Supports various game launchers, such as Gog.com, Epic Games, Amazon Prime Games
• Steam - Supports Steam games

Install any software

There are various supported ways of installing software and you should stick to the ones recommended by Kalpa Desktop.
Game launchers described in the previous section are available as Flatpaks. These are sandboxed applications that have only a subset of the permissions of the user to reduce the blast impact of malware or application defects. They also contain all dependencies to run the application.
Nevertless, you should always make sure that the Flatpaks come from a valid and credible publisher (even if they are marked as verified - always check).
You can search for Flatpaks using the Discover application already preinstalled in Kalpa Desktop. Discover provides als updates of the application in case you need it. Additionally you can further limit permissions of the application to increase security.

Tweaking runtimes

Linux provides various runtimes to run games, such as Proton or Wine.
The games launcher allow to configure them and tweak them in various details. However, nowadays this is not necessary and should be avoided to not have issues.

ProtonPlus provides some advanced tweaking and additional runtimes in case you are open for experiments. It is available as Flatpak in Discover.

Annex: udev Rules for specific peripherals

Honeycomb

Logitech Thrustmaster

InputLabs Alpakka

Annex: SElinux and Gaming

We have explained how you can enable in OpenSuSE SElinux policies for gaming here. This provides a package to be installed by the standard OpenSuSE package manager and we recommend to use this package. This annex explains what this means in detail and alternative solutions.

You can alternatively enable the following SElinux policy:
sudo setsebool -P selinuxuser_execmod 1
The setting selinuxuser_execmod allows for all unconfined libraries to do text relocation. The parameter "-P" makes the setting permanent (without it you have to enter it after every restart). You can of course at anytime set it back to 0 permanently.
You can find the background of this setting and its implications here. To summarize it: It is acceptable to enable it for a gaming PC, if you need to run Windows games.