I assume I should get rid of most of the swap. I also read somewhere to increase… swappiness of zram?
Odd consideration, but… I use 16Gb of ram and I have zero swap space and I’ve never seen a freeze in the three years this system has been assembled.
It could just be the way I tend to use my PC, light photo manipulation, some audio editing, some gaming just not AAA. I’m never stressing my system unless I’m opening a compressed file or rendering a video.
Odd consideration, but… I use 16Gb of ram and I have zero swap space and I’ve never seen a freeze in the three years this system has been assembled.
You won’t see big problems until you use most of the ram, then you’re toast. Also Linux (if that’s what you’re using) prefers to have more cache at the expense of swapping out pages. There’s a lot of rarely used code on many apps that can be safely swapped out to get you more cache.
I used a work laptop without swap for a while and it was very anoying. RAM intensive tasks were Rust IDE integration and compilation, data engineering, …
Exactly the same for me, 26Hb, no Swap installed, never had a freeze or a problem in the two years using Arch
Those defaults sound pretty sensible. I have as much swap as I have RAM because I set things up to hibernate. I believe pop os has the swappiness set to 180 for using the zram.
Should I lower swap? How do I change the swappiness?
Have a look at this for info on swappiness. As for your swap, if it’s not causing you problems, it can’t hurt to have it.
There’s some instructions here but basically:
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sudo apt install zram-config -
append to end of
/etc/sysctl.conf:vm.swappiness = 180 # disable swap readahead (since using zram swap) vm.page-cluster = 0Can check these have been applied with
cat /proc/sys/vm/page-clusteror.../swappiness
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Why would you get rid of the swap? Having swap space should never hurt. Swap can sit empty when it’s not needed, and some memory pages are rarely used, so you’ll hardly notice if there swapped out.
Only to much swapping is annoying/slow. This happens if you run out of physical RAM; mostly independent of your swap size.
You can listen to the experts here for how to fine-tune the parameters (swappiness). Linux (as most operations systems) is built with the assumption that swap > physical RAM exists. Linux can run without swap, but the kernel runs into a huge problem if RAM becomes nearly full and has to kill processes. Usually adding swap is the better option.
Zram usually has a very high compression ratio - around 4:1 for lz4 and 6:1 for zstd. You can set zram to 40-50 GB. It will still use less than 1/2 of your ram.
Zram has an option to write poorly compressible data to the disk instead of storing it in the ram. I would split the swap partition - 3 GB for zram writeback and rest for ordinary swap.
