Hi!. Currently running Linux Mint 22.1, but i suspect it's not strictly a distro issue. This laptop was running VERY well but was outdated, running Mint 19.3, some things were unable to be installed because the system libraries were old (didn't expect Calibre to be one of them, figures), so i updated all the way to that moment's current version which was Mint 21.3. All of a sudden it felt like the laptop got downgraded two whole computer tech generations. As soon as i ask it to do something mildly complicated that made it break no sweat on Mint 19, it gets VERY slow, all the cores start running at max, system load increases, until it finishes doing whatever it was doing several minutes later, something between a couple of minutes when lucky, to 20 or more. Typically what triggers the issue is something on the browser (what i use the most on the computer is browser tabs and lots of terminals) but not exclusively. Thought it was the browser but replicated it on an empty Firefox profile, and has triggered with simpler stuff like the Discord client. Been trying to find the issue for a while trying to avoid a full reinstall, no luck so far.
If i were to describe how it feels, it's like there was a bottleneck on tasks being done by the system, as soon as you ask it to do something mildly complex it chokes on it and tasks accumulate. No idea if it's some kind of kernel misconfiguration, if it's some hardware incompatibility, or something else entirely, checking the changelogs of Mint all the way between 19.3 and 21.3 showed nothing i could pin this onto (or at least nothing i could notice).
The nuclear option would be a brand new blank install but I'd MUCH rather avoid that if possible, made the comfortable but now unwise choice of a single partition for everything (instead of a separate /home and whatnot as i used to do) so reinstallation would wipe it completely, if i must then i must but much rather not.
Would welcome VERY much ideas on stuff to check or try.
Edit: It's got an NVME drive, which seems to be healthy as far as i can see
Edit: When it happens it doesn't seem to matter how much RAM is free, seen it happen with only 8 of the 32Gb of RAM in use and zero swap
Edit: Found a great way to describe how it feels like: Have you done heavy video encoding on a computer that's adequate for the task but not more than that, and noticed how everything in it stalls heavily, even if there's plenty of RAM free and the computer feels like it's giving everything to that task only? Pretty much that, but for nearly everything even moderately heavy
After installing it, a tiny but relevant point is to get a nicer icon that "app name in a square", Organic Maps had a nice, RECOGNIZABLE icon, CoMaps will be glossed over when looking for it a bunch of times because of it's super generic one. I imagine it's coming since they're just starting but hope that someone does have it in mind.