I have a heatsink above CPU, RAM, and Wi-Fi card. I think I should get a fan.

I saw that it uses about 1,3 GB of memory. This means another 700MB remain. Because of this, I don’t think the cause is the memory. Also, I forgot to mention that I am also running qbittorrent for downloading, gluetun for VPN, and jellyfin and jellyseerr.

OK, I am trying to setup a swap partition right now to see if that will improve performance.