Since upgrade to Mojave, even after reboot and no active programs, 10.5G to 12 gig of Active memory already taken ? Why?

[Wildlingling]

I am trying to figure out why Mojave seems to to be taking up a huge amount of active memory on my late 15 Imac. I have 24 gig memory and even after reboot and not running anything, the Mac steadily keeps eating up memory until it get to anywhere from 10.5 to 12 Gig. I open up Chrome or safari and any other app and it quickly goes up to 18-20 gig active memory.

I can't find anything that's actively causing it. Activity monitor shows a list of processes open but when I add up the memory each is taking it comes to nowhere near the 'Memory used' total comes to. The 'app memory' seems to be the big culprit as that has the largest percentage (like 80%) of this memory total. There's nothing in the console logs that appears to explain this huge memory allocation either.

I upgraded from High Sierra to Mojave. Maybe others have seen this same reaction? I'm not seeing any posts in forums anywhere explaining this. I actually restored to a previous time machine back (still in Mojave) and it's still happening.

Any help anyone can provide would be greatly appreciated.

 

[Lufbrarunner]

My late 2015 iMac running Mojave, has 24gb RAM and with Safari, Chrome, Excel, Adobe Acrobat and VSCode open the memory used is only just over 8gb.
Do you have any background apps running (Anti Virus or malware etc.)?