Last thing I did before the problem occured was to try and update my system -Manjaro XFCE-, which I couldn’t because of “not enough space on the hdd”, something like that, I don’t recall the exact words. So I thought it’d be clever to delet the orphans packages, did that, nothing changed.
Oh I don’t know, just thought it would be at least a different type to the partition where all my private data is saved …
So what would be an appropriate size?
You can simply reduce the size of the reserved space to 64 MiB. This will have an immediate effect on your free space for sda2, without resorting to resizing partitions or reformatting anything.
sudo tune2fs -r 16384 /dev/sda2
By default, a newly formatted Ext4 filesystem will reserve 5% space, which in your case is a waste of almost 1 GiB.
Other culprits include the use of Timeshift on the same filesystem, among other factors mentioned in this thread, such as your temporary files, pacman cache, and journals.
Using Timeshift on the same filesystem is the single biggest factor, however.
The number 16384 is for 16384 “blocks”. Your blocksize is very likely 4096-bytes, so 16384 blocks multiplied by 4096 bytes equals 67108864 bytes, which equals 64 MiB.
Yes, pretty much. Heck, you can even go lower and set it to 32 MiB if you’d like. (That is, -r 8192)
It’s the “superuser” reserved space, which cannot be written to. It’s more of a legacy spillover from the older days of filesystems, in which you would need even a tiny bit of free space that the “superuser” can use to recover a full (and read-only) filesystem.
64 (or even just 32) MiB of reserved space should be fine for most modern systems.
How is your root filesystem so full, without using Timeshift on it? How much stuff do you have installed?
What are your cache settings configured as under the Pamac GUI?
The OP already said they will resize their partition (which does carry its risks), but it’s not mutually exclusive with running a leaner system that isn’t filled with excessive cruft and cache, as well as the (pointless) default 5% space reservation for Ext4 filesystems.