I'm using an old backup GUI for rsync. Yesterday I realized that 1GB of swap will not cut it if I want to play with "AI". Now the thing is, I'm running ZFS on root. And from what I've read i a nice book, COW doesn't like having swap files, and I can't shrink "partition".
Now here's a thing, ZFS has ability to send and receive datasets, and after this fuckup I will train myself how to do it in VM.
The problem was between keyboard and chair, as expected. I was making backups to a nice DAS I got myself for Christmas, laoded with x6 4TB drives in RaidZ2 pool (I got those for dirt cheap from some old datecenter pull). Now software I used is called LuckyBackup, it has lots of options, one of them was to skip cache files. I assumed that it will skip stuff in ~/.cache and cache directories in /var.
Nope.
So when I recreated my root dataset with desired size, leaving 32GB of swap (just in case, I have 64GB of RAM) I tried to boot, nope. Well, that one was on me, I changed partlabel for ZFS partition, so I rebuilt kernel image and updated zpool cache. Reboot.
Nope, logind isn't happy, so i plugged in my phone with USB tethering, fuck remembering how to connect to wireless via CLI.
Running pacman-fix-permissions script from AUR, yep it's fucked, loads of missing files in various cache directories in /usr, permissions mismatch, plus about 10 file conflicts.
After I fixed pacman files conflicts, pacman-fix-permissions resolved all issues.
Lessons learned, read documentation, duh. Also I should probably read about "zfs send" and "zfs receive commands".
TLDR. Don't be retarded like me. My system is back and running and I can play with AI without running out of memory, for now.