So, this is more an informational question. I notice that when I first start up KDE the total memory usage is around 1.1 Gig. (Using inxi -I)Startup includes apps like Insync, Dropbox, and Yakuake. Okay.

However, before I shut down, and after having closed down all the usual "discretionary" apps like Firefox, Libre, Thunderbird, etc... Basically, when I've returned to the same configuration as immediately after startup, KDE shows that I'm only using 760 to 770 megabytes.

So, my question: What happened to the nearly half a gig? Why does KDE always seem to require so much more at Startup?

Using KDE Neon 5.7.5.