If you have a 1/2gb and maybe less so with 4gb then Zram could really help with the desktop perf and mem availability.
Set mem_limit to 50% of ram, disk_size x3 mem_limit and swappiness 100.
With the oomf of the RK3399 & DDR4 zram becomes even more transparent try the above and give feedback please.
sudo apt-get install git nano
git clone https://github.com/StuartIanNaylor/zram-config
cd zram-config
sudo sh install.sh
sudo nano /etc/ztab
sudo reboot
