Fedora 34 Looking To Tweak Default zRAM Configuration

Last year with Fedora 33 zRAM was switched on by default. The setup was that using a compressed zRAM drive for swap space leads to better performance and in turn a better user experience. Some spins of Fedora have been using swap-on-zRAM by default going back many releases while since F33 it's been used for all spins. Now with Fedora 34 the configuration is being further refined.

With Fedora 33, the zRAM configuration was limited to a 0.5 fraction of RAM or 4GB, whichever is smaller, while for Fedora 34 the zram-fraction will be 1.0 and the maximum zRAM size set to 8GiB.

The change proposal outlines the plan: "Fedora 33 enabled zram by default. The size of the virtual swap devices was set so that the amount of memory used for compressed swap pages was limited to a quarter of physical memory in typical scenarios. That size is now increased to half of physical memory (zram-fraction becomes 1.0, max-zram-size becomes 8 GiB). This allows systems with small amounts to successfully launch the Anaconda installer and other programs."

This in particular should help the Fedora 34 experience for systems with minimal amounts of RAM.

Fedora 34 on systems with small amounts of RAM should also benefit from the plan to enable systemd-oomd by default for the distribution.