Swap used when plenty of physical memory is available - slows system.

English Hardware
#1

Since upgrading to 42.1, I’ve noticed that OpenSUSE tends to use a fair amount of memory - particularly baloo and the plasma shell. After a long up time, I notice up to 6 to 8 gigs of memory indicated as used by free. However, my system has 16 gig installed and free will show 8 or 9 gigs of available memory. Still, the system insists on using swap space despite the copious availability of free memory - at the moment 1.4 gigs worth. This noticeably slows the system when opening programs or changing windows. Why does this happen and is there a way to stop it?

Thanks for your help.

#2

Hi
I use the following in /etc/sysctl.conf;


# Disable swap
vm.swappiness = 1
vm.vfs_cache_pressure = 50

Mainly for SSD’s, which are all in my primary systems.
https://en.opensuse.org/SDB:SSD_performance

#3

Thanks. This helps.

#4

I have 8G of memory. At present, there’s a little under 2G free, with no swap being used.

The main times that I see swap used are when I download an iso, and when I write that iso to a USB. There’s usually still some free memory – more than the amount of swap used.

My guess (a totally uninformed guess), is that this is a priority kind of thing. What’s going into swap appears to be low priority stuff.

#5

There are now sever directories using tmpfs which may spill over into swap. The max amount of memory is fixed at mount I think and may be 1 gig for all tmpfs mounts no matter the actual memory installed. Maybe increasing the tmpfs memory might mitigate the problem