spinning-down hdd’s when they’re not in use

I’ve just been through this recently. I decided to have my 2 backup HDDs spin down when not in use (99% of the time). I ran into an issue though where I needed them to wake up for SMART tests (which SMART didn’t trigger). Tried a few things that didn’t work so just set them to spin all the time. There’s about a 1-2w difference when they’re spinning all the time. So it’s just not something worth worrying about IMO (In the UK with high energy costs that comes out to 2.5 pence per day roughly).

When I built my NAS I intentionally bought the latest gen cpu, but kept it in to the 65W series with a GPU chip onboard. It’s an AMD Ryzen 5 7600 6-Core @ 3800 MHz. My coral usb does frigate and the integrated graphics chip does jellyfin just fine. I started with ssds, but half of them burned out pretty quick, so I replaced them with spinning rust. But, as-is it can run for an hour on my desktop grade UPS before it shuts down. My proxmox cluster is old laptops that mount an NFS drive from my NAS. So, yes, I took power efficiency into account.

I made a post about this a while back because I had some of the same concerns about power usage. (https://lemmy.world/post/41185625)

As most people are telling you, as they told me, ‘get better, more efficient equipment’, which is great advice if you are buying, but not so helpful if you’ve already bought. First thing I’d do is get a watt meter to get a baseline of what is being consumed. You can get watt meters from Amazon, or your preferred big box vendor, for cheap.

Once you have the baseline, then you can go about fiddling with Linux and your server, to find areas of excess power consumption. Please note tho, you’re not going to tame a $100 a month server down to $20. That’s just outside the realm of reality. However, every little bit helps. Go into your BIOS and check if there are power saving options there as well.

I know this will go against the grain, but I have a cron that powers off the server every evening before I retire. I am the only user of my services and I have no midnight, mass Linux ISO downloads going on, so I couldn’t justify having the server run for 10+ hours idle, consuming electricity. Electricity here is fairly cheap and I also have solar panels, but still, I think it’s worth the effort to be prudent with your resources.

In the end, the final tally was that I spend around $35 USD per month in electricity, which is far less than most people spend on a hobby.

Newer hardware that has lower idle consumption mostly. I’ve found there’s not much to do on a typical setup as far as software optimization, as most OS’s are already set up for pretty low power usage while idle.

HDD sleep can work if you don’t have anything accessing the drives, but with all the stuff running on my server there’s basically always some kind of activity going on so they never sleep. Less HDDs is the answer for me, I just have 2 large drives in a ZFS mirror.

My HP box with an i5-7500 idles around 15-20W which is decently low, but I also have 2 PCs with i3-7100u mobile chips that idle at 1-2W with 32GB of RAM and an NVMe SSD, which is wild.

Avoiding enterprise gear is key, it’s extremely power hungry.

Added solar and a battery. I don’t worry too much about the power use as a result.

My video server runs from 6 pm to 1 am. No need to run always.

Letting go of older inefficient hardware is no 1.

Why run a 200w server when a 30w mini PC or 10w pi can run a dozen containers

As someone else here mentioned, isknf powertop can significantly reduce consumption at idle, which helps.

In the world of servers, though, unless a device is only accessed once a day, it’s tough to get the HDD to spin down.

I got a power-efficient mainboard and PSU. I think that’ll be the lion’s share. And I don’t have any unnecessary stuff like a GPU or extra stuff connected.

I ran powertop and adopted the recommendations to set the various buses, peripherals and devices into powersave mode. That does a few Watts here and there. CPU of course is also allowed to save power when idle.

And then I made the harddisks spin down after 40min of not being used. Or something like that. So they’ll automatically spin down at night and when I’m not using them. As spinning hdds consume quite a lot of power if you have multiple of them and compare it to the 15-20W or so the rest of the computer uses. The operating system is on a SSD.

Do you have any idea what your hardware is actually pulling from the outlet? Maybe it’s not that bad after all?

Mine is pulling around 55W from the wall in its “normal” state. Meaning two 3.5" HDDs spun up, and a bunch of light services running. Which is squarely in “not great, not terrible” territory.

Apart from flipping the power saver switch on the mainboard I haven’t done anything to save power. I haven’t checked if that’s doing anything either. It’s a 3rd gen core i5 iirc, which isn’t great at idle power consumption, so maybe that switch is doing something…

I also haven’t had any luck with getting the drives to spin down reliably anyways, and afaik it’s better for them to just stay spinning so I haven’t bothered much to change that.

I had to start over anyways, so I choose SSD only. Pricier of course, but I don’t need a terrible lot of space anyways.

When I still had HDDs, they were usually used once a day for backups, and I spun them down after that.

Optimizing power profiles and C states makes a little difference, but planning with efficient hardware from the beginning is the most important thing. Don’t use your old gaming PC if you care for power efficiency.

I use powetop on laptops to recommend config optimizations, it could run on a server too.

hdparm can configure HDDs to powerdown, but I’ve never had any success using it on my router.

In theory I think You could use WoL and have your router wake a device before sending traffic but I haven’t seen any guides for doing this so maybe I’m missing something.

When building you own servers from consumer hardware this is a bit difficult, but getting a PSU that actually fits to the power use profile of the server seems to make a difference. Sadly it is hard to get small PSUs with sufficient SATA power connections.

Dell Thin Client type machine with a 2TB SSD of the essentials. Backs up once a week to my gaming desktop. Has enough horsepower for Homeassistant, Jellyfin, adblocking. Enough fast USB for two 2.5GBE. Upgraded to 16GB RAM before the crisis, but could make due with 8GB. Cheaper than a raspberry pi for only a few extra watts.

Acronyms, initialisms, abbreviations, contractions, and other phrases which expand to something larger, that I’ve seen in this thread:

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