wsl2-xwin-audio

Tips to setup GUI in wsl2.

Introduction

See Awesome-wsl

The following assume that the Ubuntu 18.04 distros CanonicalGroupLimited.Ubuntu18.04onWindows_1804.2018.817.0_x64__79rhkp1fndgsc.Appx has been downloaded.

Installation

The followings are executed on a git bash shell. They can be easily translated to powershell script.

Install: powershell "Add-AppxPackage .\CanonicalGroupLimited.Ubuntu18.04onWindows_1804.2018.817.0_x64__79rhkp1fndgsc.Appx"

Default to wsl2 instead of wsl1: wsl --set-default-version 2

Verify your installation: wsl -l -v

(Optional) Create and go to another directory to store wsl filesystem (see issue):

wsl --export Ubuntu-18.04 ./ubuntu-wsl.tar
mkdir ubuntu-wsl
wsl --unregister Ubuntu-18.04
wsl --import Ubuntu-18.04 ./ubuntu-wsl ./ubuntu-wsl.tar

Create a user as your-user-name: powershell "ubuntu1804 config --default-user your-user-name"

Fix Ram Issue

Open wsl shell.

Run sudo crontab -e -u root, add the following to drop_cache automatically every 15 min`:

*/15 * * * * sync; echo 3 > /proc/sys/vm/drop_caches; touch /root/drop_caches_last_run

Assume you use zsh, add the following to ~/.zshrc (~/.bashrc if you use bash) to start cron service automatically:

[ -z "$(ps -ef | grep cron | grep -v grep)" ] && sudo /etc/init.d/cron start &> /dev/null

To allow starting cron service without asking by root password, run sudo visudo and add:

%sudo ALL=NOPASSWD: /etc/init.d/cron start

To check when did you last clear your caches, run:

sudo stat -c '%y' /root/drop_caches_last_run

(Optional) Leave wsl and open Git Bash, limit the memory usage by placing .wslconfig (sample) to ~/.wslconfig.

Install GUI (X Server) and Audio (PulseAudio)

There are a few ways to install X Server and PulseAudio for Windows, my choice here is the good old Cygwin.

Install Cygwin and add the directory of cygwin.exe to your environment variable PATH. I recommend doing this via scoop: scoop install cygwin.

Check this in the wsl shell: which cygwin.exe

Run cygwin-setup.exe, install xinit, pulseaudio, and pulseaudio-module-x11.

Install packages in Ubuntu wsl:

sudo apt install x11-apps ubuntu-restricted-extras

Configuration

Reference: Cygwin/X OpenGL and PulseAudio.

Copy xpa and killxpa to ~/bin and do export PATH="$HOME/bin":$PATH. Make sure that you can call cygwin.exe.

Export the following environment variables:

# x11 opengl rendering options 
export LIBGL_ALWAYS_INDIRECT=0
export LIBGL_ALWAYS_SOFTWARE=0

# display to Xserver, sound to audiopulse server
export DISPLAY=$(grep -m 1 nameserver /etc/resolv.conf | awk '{print $2}'):0.0
export PULSE_SERVER=tcp:$(grep -m 1 nameserver /etc/resolv.conf | awk '{print $2}')

xpa: run X server + PulseAudio

killxpa: kill X server + PulseAudio

Add the following to run xpa automatically when you start the terminal and run killxpa automatically when you close the terminal.

# run when start if not in tmux
if [ -z "$TMUX" ]; then
    xpa &> /dev/null
fi

# run when exit if not in tmux
if [ -z "$TMUX" ]; then
    trap "killxpa" EXIT
fi

See .zshrc for a sample configuration.

Test

Test X Server - run: xeyes

Test PulseAudio - run: paplay /usr/share/sounds/freedesktop/stereo/bell.oga

Fix Color Display

Color display in /mnt and tmux can be weird in wsl2.

Add (to ~/.zshrc or ~/.bashrc if you use bash)

# Fix directory color in /mnt
export LS_COLORS='ow=01;36;40'

and (to ~/.tmux.conf)

set -g default-terminal "xterm-256color"