I recently published a post with my template.wslconfig configuration file. But I don't think simply sharing the configuration is enough. From my experience, I know that information is better perceived when accompanied by real-world usage examples. So, I decided to write a series of posts explaining the settings in this file in more detail and providing examples of their use.
In previous posts, I published a template for wsl.conf, the internal configuration file for WSL instances, and explained how it differs from .wslconfig. Now it’s time to take a closer look at .wslconfig. This file globally manages the Windows Subsystem for Linux itself and affects all instances within it.
Canonical has announced support for packages optimized for the v3 CPU architecture. Starting with Ubuntu 25.10 (currently in testing), it’s now possible to install and update packages built for this architecture.
At the moment, v3 packages are still being rebuilt, so not all of them are available yet. Testing is also incomplete, and users who upgrade may encounter some issues, these will be addressed by the time Ubuntu 26.04 LTS is released.
Since I started using WSL as my primary environment for learning and development, I began collecting the settings of its configuration files. By gradually testing and verifying the behavior of each setting and its dependencies, I compiled a documented and ready-to-use wsl.conf template, which I apply across all of my instances.
My WSL overview begins with a look at its main configurations. These files provide the big picture of what WSL can do and how to control its behavior, both for the overall WSL environment and for individual Linux instances.
Throughout this text, I will use the term instance to distinguish between two related concepts. A distribution is an archive containing the rootfs of the operating system being installed. An instance is a system that has been installed from a distribution and is ready to run (or already running).