Ubuntu 20.04 high memory usage when all apps are closed

Question

All my apps (except terminator that runs htop) are closed.

OS is taking more than 6GB of memory. Crazy how high this is!!!

See screencap showing sudo htop.

Before the screencap, I've killed a bunch of other apps:

sudo pkill -f gnome-calendar
sudo pkill -f evolution-alarm-notify
sudo pkill -f evolution-calendar-factory
sudo systemctl stop snapd

Also restarted gnome-shell to reset it's memory:

alt+f2 + r + enter
or
killall -SIGHUP gnome-shell

* Had this problem with 19.10 as well.

I disabled gnome-extensions using Tweaks ui and still almost 7GB of memory consumption without any app open. — AlikElzin-kilaka, Dec 31 '20 at 09:50
something useful here? https://askubuntu.com/questions/1036441/ubuntu-18-04-gnome-shell-high-cpu-usage — nobody, Dec 31 '20 at 10:37
I don't know htop, I'd suggest to use "ps aux --sort -rss" or "ps aux --sort -rss | head -20" — Koen, Dec 31 '20 at 11:15
you can also do a free -m -- or read this https://www.linuxatemyram.com/ - you can free some cached disk memory with "echo 3 | sudo tee /proc/sys/vm/drop_caches" but it's not really useful — Koen, Dec 31 '20 at 11:23

score 0 · Answer 1 · answered Dec 31 '20 at 11:29

Some memory may be used to cache some disk space - it'll be freed automatically if needed by programs

do a

free -m

to see real free memory : "available" column

How do I stop Linux from doing this?

You can't disable disk caching. The only reason anyone ever wants to disable disk caching is because they think it takes memory away from their applications, which it doesn't! Disk cache makes applications load faster and run smoother, but it NEVER EVER takes memory away from them! Therefore, there's absolutely no reason to disable it!

If, however, you find yourself needing to clear some RAM quickly to workaround another issue, like a VM misbehaving, you can force linux to nondestructively drop caches using echo 3 | sudo tee /proc/sys/vm/drop_caches.

see more here : https://www.linuxatemyram.com/

When I start some heavy apps, like Intellij IDEA and many chrome tabs, the memory of the OS stays very high. Memory isn't being "freed" for the apps I started. — AlikElzin-kilaka, Dec 31 '20 at 14:15

Ubuntu 20.04 high memory usage when all apps are closed

1 Answers1