Canonical posts instructions for running Ubuntu Desktop on Raspberry Pi 4 2GB
Canonical posts instructions for installing Ubuntu Desktop on a Raspberry Pi 4 with 2GB of memory. Zswap is used for this. Previously, Canonical recommended that users run Ubuntu on a Raspberry Pi 4 with 4GB or 8GB of memory.
Canonical says in a blog post that from Ubuntu 22.04, which is scheduled for April, it wants to make its OS usable by default on the Raspberry Pi 4 2GB, although by enabling some settings this is already possible with current Ubuntu versions. The company reports that it uses zswap, a type of compression tool.
Ubuntu, like many other Linux distributions, uses swap files. This saves files that do not fit in the ram on a storage system, such as the microSD card of a Raspberry Pi. With zswap, files that are moved to the swap file are first compressed. Then it is checked whether the file still needs to be moved to the swap file, or whether it is small enough after compression to remain in the ram. That should provide better performance on systems with low memory.
So Zswap is added to Ubuntu 22.04 by default, but Canonical also puts installation instructions in its blog post that will allow users to enable the feature for current Ubuntu releases. Users just need to type a command in the terminal and then reboot their system and zswap should work. Then users can enable z3fold and lz4 to further extend the function, which should provide better performance on a Raspberry Pi 4 2GB. Canonical also offers instructions for this and those optimizations are also enabled by default in Ubuntu 22.04.