apt-fast VS LxRunOffline

FYI: I/O is indeed a limiting factor but apt is not very efficient and updates can get a lot faster with wrappers like apt-fast which download and process in parallel.

If picking another mirror doesn't speed it up, I can highly recommend apt-fast.

Use apt-fast

just as a tip: if your distro uses apt just install apt-fast (its a wrapper script for apt/ apt-get which adds multithreading, etc)

apt-fast added to improve download speed and reliability.

You can also increase the download speed by downloading multiple packages at the same time. apt does not have support for this built-in but there is a wrapper called apt-fast that does this: https://github.com/ilikenwf/apt-fast

Are you a developer? The way I managed to get WSL was when an IT support person updated my Docker Desktop and enabled the WSL 2 backend. Unfortunately installing a distro didn't work but I managed to work around that using LxRunOffline. However now I can install any distro using "wsl --install".

You could run wsl --export to backup your Ubuntu env. Or there's a tool called lxrunoffline that could do the same thing too.

I recommend the LxRunOffline tool. DDoSolitary/LxRunOffline: A full-featured utility for managing Windows Subsystem for Linux (WSL) (github.com)

The script will download the LxRunOffline distro manager to bootstrap the installation. Install times will vary depending on system performance and presence of antivirus software. A fast system with broadband Internet can complete the install in under 10 minutes and most machines will complete within 20 minutes.