Hi,
Do you have suggestions for kernel tweaks for getting the most out of a RAM limited system?
I am running a service requiring 2GB of RAM (netbird) on a VPS which has just 1 GB of memory. I am doing so because I am a stingy bastard and I use only free VPSs for my personal use so I get what I am paying for.
Because of this hardware limit in about 12 hours from service start I begin swapping a bit too much. This would still be manageable but soon the hypervisor gets really pissed and steals up to 90% of the CPU. So the only solution so far is restarting the docker containers every 12 hours (not great, not terrible).
Looking to improve this, Iam now experimenting with ZRAM and swappiness and it seems some benefit can be achieved by using some of the Linux kernel feaures. Is there anything else I should look into?
I think the advice should be taken to heart here — you're dealing with a userspace problem but you're trying to get the kernel to make it all better.
You've already mentioned the two big things, compressed RAM and swap; optimizing userspace (or paying for more RAM) may be the only option at some point.
If you want to get creative, is there a reason you can't use a local computer for some of these services? An old raspberry pi or similar could potentially run some of your services. You could run some containers on your home server and call it a day. Quick search turned up this https://www.linuxserver.io/blog/routing-docker-host-and-container-traffic-through-wireguard