This is an old desktop I use for some small self hosting services. I never use all my RAM and I don't see any RAM spikes other than when I install/compile things which I haven't done in months. I restarted the machine a couple of times, but the SWAP will eventually go right back up to 100%.
I have an Ubuntu server/yunohost setup and found: https://askubuntu.com/questions/157793/why-is-swap-being-used-even-though-i-have-plenty-of-free-ram
My cat /proc/sys/vm/swappiness value is indeed 60. Im not sure what would reduce the SWAP space usage.
Would changing this swappiness value help? Anyone come across this issue before?
EDIT: Found out what it is, its the matrix server that is running on the system. Its taking up a significant amount of swap. Found out via:
smem -s swap -r -p
turning that off, the system is now using 90% less SWAP.
/opt/yunohost/matrix-synaps was the process.
except when not, like when I just copied a multi GB file, it was cached in RAM to be not read again for long, but at least half of my running programs are swapped out. Additionally if swap is o SSD, it has put totally unnecessary wear into it by doing this
That's why you can adjust swappiness, or designate a different high-endurance storage device for it.
my swappiness is 0. yet my swap usage isn't. plenty of "available" memory (as in, multiple GB)
good luck with that on a laptop. maybe the swapiness setting could just work sensibly
“sensibly” “intuitively” and “performant” are all different objectives and I assure you kernel devs working on such a central subsystem are primarily optimizing for one.
the meaning of zero really shouldn't be an objective thing. it means: don't do that
the kernel is literally eating my soldered eMMC chip