swap VS systemd-swap

As a bonus, the systemd-zram-service's scripts will create zRAM devices based on the number of your CPU cores. This is problematic as it's a deprecated practice, and can also cause an issue on some multicore CPUs. Basically, we already have "multi stream functionality" since kernel 3.15. And since kernel 4.7, regardless of the value passed to [max_comp_streams], zRAM will always allocate multiple compression streams - one per online CPU - thus allowing several concurrent compression operations.

Historically, Linux has created an additional (fixed-size) swap partition or file. In case you mention you get OOM. But for some time there is a great project systemd-swap creating hybrid swap space. You can even find it in the official Arch Linux Community repo.

There is also systemd/zram-generator that allows you to create and manage swap devices more easily. And Nefelim4ag/systemd-swap (abandoned?) that automatically creates swap files and resizes them based on RAM usage.

SwapFC - https://github.com/Nefelim4ag/systemd-swap

That sound like what systemd-swap does. Apparently, hibernation is not quite working yet, though.

https://github.com/Nefelim4ag/systemd-swap

Disclaimer: I couldn't find anything relating to SwapFC other than from the README of systemd-swap. What I've written above is just based on the one-line description of SwapFC, as well as prior knowledge of zswap and zram (obtained from the Linux Kernel docs).