Can't run prometheus, so what
I've got a gen9 microserver at a remote colo, 8W idle, 16GB total. Prometheus alone wanted 2GB just to exist. Scraped it.
Tried netdata. 150MB. Better. Still annoyed me.
Ended up with node_exporter + a 20-line shell script curling to a central box. 12MB. Survives on a 512MB GreenCloudVPS instance without swapping.
The real answer is always "measure what you actually need" not "run what everyone runs"
visit twice: install and decom