In an effort to make the homelab more environmentally friendly, I have started to explore ways to conserve energy consumption. I always see a lot of considerations for choosing equipment that sips power, but other than avoiding enterprise power hogs and very old equipment, I don’t see a lot of advice in how to tame the server(s) you may already have.

So far I’ve looked at:

  • TLP: Adjusts CPU frequency scaling, PCI‑e ASPM, SATA link power‑management
  • Powertop: Used to profile power consumption and has a tune feature sudo powertop --auto-tune
  • cpufrequtils: Used to manage the CPU governor directly
  • logind.conf: Can be used to put the whole server to sleep when idle

Since I am the only user of my network, and since a lot of times the server sits unused until I want to engage maybe listening to my audio collection via Navidrome, or perhaps I’m working on some automation in n8n, et al, there’s no need to be at max power 24/7.

So besides just powering off and on the server, which would work but not be quite as elegant of a solution, are there other ways you have come across, read about, deployed on your own server?

ETA: Thanks for everyone’s input. I realize that the ideal scenario is to have more energy effecient equipment. Sometimes tho, this is not a ready made solution due to many constraints. The exercise was to try to squeeze out every last little power saving option I could, without obviously replacing equipment.

Many thanks.

  • Admiral Patrick@dubvee.orgEnglish
    7·
    4 days ago

    I downgraded from used enterprise gear to those ultra small form factor PCs. They sip power well enough on their own that I haven’t really bothered tuning anything. I suppose I could cap the frequency with cpufrequtils and set the governor to conservative rather than on-demand (I do this with my battery-powered RasPi projects) but I’m not sure how much difference that’ll make for my servers.

    In the past, I had Docker Swarm setup and automation to collapse the swarm down to a single machine (powering the other ones down and back on with WoL) but that was more trouble than it was worth. On average load, the USFF PCs run at about 15 watts and don’t usually peak above 30 unless they’re rebooting or doing something very heavy. Even transcoding doesn’t break 20 watts since I’m using hardware acceleration.

    The biggest power savings I found that was worth the effort was to just get rid of the enterprise gear, switch from VMs to Docker containers where possible, and get rid of stuff I’m not using (or only run it on-demand).

    The only remaining enterprise power suck I have left is my managed switch. It’s a 2005-era dinosaur that’s loud and power hungry, but it’s been a workhorse I’m having a hard time parting with.