How Much Power Can You Save by Putting Your NAS HDD's to Sleep?

The power supply pulls 14.9 watts with no drives or anything else plugged in and as noted in the video the Zima board is powered by it's own power supply.

I think its advantageous to put them into standby mode. Its better that way when you have nothing to do with it for hours on end.

I watch your videos and learned a lot about homelab stuff. But as you are leaned toward more professional-server stuff(beefy, power hungry things), I think you made some wrong choices for test setup here. PSU efficiency really matters at low power load set-up, and not all gold or platinum psus are efficient at low power(around 20w range). You can't say spindown 4 disk saves only 9watt like that without some efficient PSU. you need to get efficient PSU first. Corsair RM650 or rm750 are known to be pretty power efficient, but now all the corsair PSUs work well at low power load.

I made some diy nases recently. x86 6-9th gen stuff with good(efficient) PSU, and my recent nas(i5-8500, corsair rm750, asrock z370m, 2nvme, 4*2tb sata ssd, 2*12tb hc520, 3*18tb hc550, 1*8tb wd red) pull about 19watt at all hdds spundown, pull about 60watt at all hdd spunup. This is more than double powersave compared to your result. And my system is not even really 'power efficient' compared to some machines i saw online.

Just based on sheer physics: speeding up and slowing down takes more effort therfore more strain on the moving parts than a constant speed. I really would be interested in long term data though. Backblaze?

This needs a final comment after watching the latest live where Tom addressed this topic.

I don't know if this is Hanlon's razor or not, but trust is completely gone at this point.

In order of how he talks about it in the live video:
1. The use of the killawatt is not the problem.
2. The Seagate tool is on github as openSeaChest by Seagate themselves, open source under the MPL.
3. "Idle Watt average of 5 Watts" - Tom even read that wrong, it says "Idle_A" average 5 Watt. That's without spinning down the disks!
4. Why didn't Tom bother to show the full table in the full documentation? I even pointed out where to find it!
5. Ranting on about 50 Watt savings is BS. That would be 438kWh per year. Another BS number since at least the disks gets used at some point during a year. But it proves a point.
6. Now he talks about data centers, while in the video he uses a Zima board with loose disks!
7. ZFS workloads can be scheduled.
8. Use case is lost, nobody is talking about spinning down disks you need online. That's just plain whataboutism.
9. The average homelab users he talks about would probably see the most savings of spinning down, as their usage probably is not 24/7 but more like a few evening hours.
10. The rest of the system using more power could be true, but then also more likely false. Google "Die sparsamsten Systeme (<30W Idle)"

To reiterate.
The problem is that he claims power savings of only 9 Watt while it should've been 16 Watt. The difference here is in the inefficiency of the PSU he used.
Therefore his conclusion is wrong as a general statement. But for some reason he doesn't seem to be willing to admit that.
The reason for him only getting 9 Watt is because he uses a really bad setup (methodology) and wasn't transparent about the inefficiency of the PSU.

Anyway, this is xkcd number 386, someone is wrong on the Internet, so I've no hope that this ever will be sorted.

At this point I'm just gonna unsub, as I wrote, trust is completely gone at this point.

The wear on the drives is negligible. Over 40 drives in a decade in use not a single fail. It's a backup of a backup system. Power on do job (2-4 hours) power off. The primary backup has more disk failures with 7x24 usage. It's enterprise stuff in a proper datacenter.

This was very interesting!!! Thanks!

These drives have a slower spinning mode, so the device starts much faster in this mode. You should also test it for comparison.

If no access after 2 hours. Sleep mode in Florida. To save electric cost seeing am running 15 of them

hmm my old 4tb hgst drives used about 70 watts switched the 4 drives to two 8tb i saw 40 watt drop i had no idea that hdd got more efficient since 2008 nice having ecc built into the hdd also

Been meaning to buy a new NAS enclosure to run TrueNAS instead of keeping using and old desktop also because of power efficiency, plus a bump in performance... but still wasn't quite there considering spinning down drives. Will see about wake on lan instead perhaps. I don't need it running all the time.
Just that my old desktop is just too old. xD Intel Haswell.
I did the whole stupid thing upgrading it before considering to get something new... the PSU was blown so I got a new one, procured RAM for it, got a new network card because the integrated ethernet was behaving weirdly... and then my power bill came and holy sh*t. xD

I've been using power down on hdd since 98 and guest what, they are still working 🤔 Might be the consumerism bullshit at play here 🤭

in a world, where wattage and amperage are a thing... there also must be kilogrammage/poundage, degreesage, lumenage, secondage ...

Interesting topic. This is something I dealt with extensively not only because it saves power but also because I have my home lab at my desk and I need it to be quiet.

My home lab with one ATX Fujitsu Siemens with an i3 6100T and an Optiplex MFF with an i3 7100t will idle at 37 Watts. It only spins up my disks when doing a backup once a day. I have 4 HDDs 2.5" and 3 HDDs 3.5". When they all run simultaneously they will consume double or triple the wattage. My home lab would cost me 120€ a year with my spinning down measures so I would say it's worth it. Especially when you use (old) consumer grade disks.

I think that the BRAND of the drives can make quite a significant impact on the results given that the data that we already have from Backblaze, for example, already puts Seagate at a higher AFR compared to the other makes/models.

That being said -- on my 4-bay QNAP TS-453Be NAS, when I spin down the four HGST 6 TB SATA drives I have in there, it will drop down from ~50 W down to ~17 W.

So, the power savings that comes with spinning the drives down ends up being quite a bit more substantial.

On my main Proxmox server, however, where I have 36 drives, the chances that I will be able to actually spin down the drives is pretty much next to zero, as there is ALWAYS some disk activity going, for a variety of reasons.

for me, not worth wear and tear of spin up/down for the small power savings. cool experiment though, good to know

Good video, right to the point thanks!

Take at look the german Unraid community. There power usage is a big thing because of the high electricty costs. I also use a unraif nas by myself because oft the concept oft spinning down all the disks that are not currently in use.

I am sure other power meter devices are available, but it is curious that "Kill-a-watt" devices don't seem to be on sale in Europe. Pity, since those ones look nicer to use than the generic ones available here.

Good video, maybe you should run a few of those experiments, and I a year or two tell everyone what the result were

I think this test is a bit too narrow in scope. I understand you're trying to refute a certain specific claim about wattage, but there should be a lot more to it. As another commenter had mentioned - there's going to be a significant noise & temperature difference even in a scenario of a small number of drives where power savings won't be a big factor.

What should be looked at is the option having both SSD and HDD in separate arrays,
SSD array always on and the HDD array only at certain times.
Should be easy to implement and test in two different NAS systems, might be worthwhile to also test a jugaad of this in a single system.
In a scenario where you might want a few tens of TB "to exist", but you don't need more than maybe 10TB at constant-availability then the total difference can be significant.

Love this test!! i have missed these little nerdy things from Tom! like when you put electricity directly to RAM on a free-nas server.

For user facing systems, we don’t spin down the drives. After some experimenting we got lots of user complaints about the server was “always” super slow. Totally different story for backup and non-user systems.

More than watts, it's heat and noise when you start to have a fair amount of drives.
I moved from TrueNas with always on raid array to Unraid with selective spin up/down.
The difference was massive on the heat side (about 10c in my ventilated server closet)

I experimented with shutting down the drives with Truenas but did not like how long it took for them to spin back up and provide data. Especially since they also store my Plex library. Clicking on something in Plex would leave you with a spinning circle for 30 seconds or so until the drives were back online. Went back to leaving them running all the time.

Entire shutdown is definitely the best way. I have my NAS set to shutdown around 10PM and BIOS configured to turn on an hour or two before I'm "up and at it".

I did experiments like this when I worked at Netapp. It was a long time ago..back when 4TB drives were the largest drives ever made. I didn't see any difference in longevity. It was the quality controls of the manufacturer that determined longevity more than anything..that and temperature. We experimented with sleeping drives because the cost of running our lab each day with HVAC was astronomical, thousands of dollars each day.

I think the wear and tear depends on the use case. I've set up mine to sleep after 3 hours of no activity which saves it from frequent spin down and spin up intervals while also saving on wear for longer inactive periods.

My backup NAS is automatically awake for 12 hours a week when all the backup/maintenance magic takes place. My feeling is that it's is adequate to my usecase

We had mailing servers and machine computers run scsi 24/7. Only shut down for total power lost, lasted 10yrs. We used unix5 on machines and windows server on the Dell server. Power on was more critical than saving power or you wouldn’t get your credit card bill, gas bill, electric bill, or in some cases, your paycheck and your tax return

For the longest time i didn't spin down my drives, but I've recently reorganized my storage so very few things actually need spinning rust, and most is in flash somewhere. Another problem was the dreaded issue that SMART reads for some reason keep them awake, but i digress.

The 6 drives home-server normally uses 95ish watts with them spinning, and this drops to around 60 now. Electricity is relatively expensive here at over 0.40€/kWh so this saves over 100€ per year. Should've done this a long time ago.

I have 8 HDD, 5 SSD setup in a 6 core 11500 NAS. One drive on its own might get accessed over the span the of the day. The entire server idles at ~62W GPU & all. If I ask the drives to stay spun up I'm looking at about 110W. My other server used to be run off a 65W chip and had a system idle of 60W with 14 disks, with the disks spun up it would idle at 144W. What's more important though is that it was not striped storage (other than the SSDs). The spike in power doesn't mean anything for the power bill it's transient and I feel like some people are going to take this as an 'um-actually' later (however it's good that you mentioned it but I was hoping you would mention it in regards to wear)

If you're running striped storage it's a totally different situation to a JBOD. When you ask that striped pool to sleep then wake for rights you have to deal with the amplified vibrations from all the drives waking at once plus the huge current sag. However in a JBOD scenario where each is written to individually or just X drive + Parity drive, it makes sense.

Instructions unclear HDD is sleeping with the fishes

Comes at the very right point in time. I was just about to buy 4 drives for my home nas.
I would also be really interested in how ZFS reacts to drive being spun down or how to tune it to allow longer timeouts.
Or Will a read/write cache nvme allow the drives to respond later.
Moreover the noise floor of exos vs e.g. ironwolf drives in different power states is very important to me. I can read the dB values from the data sheet but don’t know if I will hear it while sitting next to it 😅

With my Synologies and them getting drive sync, and hyperdrive backup, a slew of bit torrents. I think maybe I have 2-4 hours a day when MAYBE they aren't active. Turn off the lights when your not in a room! I do have a Sonoff 31 running tasmota on most of my house. Espescially now with the holiday lights. My switch rack with 3 switches, fiber modem, router and an oscislating fan use more power. and I'm not shutting those down. IMO!

Before I watch, I'm just gonna say my HGST drives don't respond to "spin down" commands from my experience. If so, I'd totally do it because those 60 drives are pulling a constant 515W from the wall.

Two identical backup systems would be good test 🤔
One that always spins and one that puts the drives to sleep. Identical backup operations for both systems and a whole lot of time…

I have an Unraid server with 20 drives, I have the drives set to spin down after 30 minutes of no activity. The server pulls about 150W when the drives are all spun down and over 270W when they are all spun up but idle. It's mostly used for Plex and with the way Unraid works it only needs to spin up the drive it's reading from, so I ensure that each shows episodes are on the same drive together so it's not jumping from drive to drive. I have had no problems with excessive drive failures since enabling spin down.

Thats why I ended up going back to Mergerfs+snapraid. Most of my data does not need to be spinning around 24/7. I for example, cannot sleep any drives. I have on my servers about 60+ services running, so it would be accessing, reading and writing 24/7 if I did one-stop solution, thts why only media is on HDDs(mergerfs) and everything else on NVMe raid. Then I can benefit of each drive sleeping seperately when not in use.

Wow, what a coincidence: yesterday I calculated the power consumption of 10 HDD (3.5) or SSD or NVME drives. And here's a surprise: 1 NVME disk is fast (Kingstone Enterprise) but can also consume 14W of power! For comparison, SSD (also Kingstone Enterpise) consumes 2W peak. 🙂

I would save a lot of power and win a lot of comfort if my unifi gateway could sent Wake on LAN packets. My WoL for my remote PC is currently running on my NAS in Home Assistant. If I could power off my NAS, and wake it with WoL, that would be great.

We want to save energy. So the term watt-hours should have been used at some point. Instead we only talked about watts which is instantaneous power. I would have expected a result something like, "With the drives spun down we are saving X watt-hours per day but a drive powering up requires more power for X number of seconds therefore to make this break-even the drive must idle for X seconds/hours/days/whatever on average before each wake and anything longer than that is savings."

So I don't think we have learned anything useful here as of yet.

Thanks for the numbers. Off topic but curious - where has the homelab show podcast gone? haven't seen it in a long time.

What about PSU inefficiency, how is that taken into account?

I run the latest TrueNAS with 20 HDDs on a 7900 12 core CPU w/128GB DDR5. I spin down the drives after 2 hrs of inactivity which seems a reasonable compromise of power savings and wear and tear. Within +/- 10% my idle power usage is 100W and under read/writes is 200W (convenient that the numbers work out so well). I keep my NVME drives always on (of course) so no problems running Docker apps which only write to these. It is a good compromise. No bad HDDs after 3+ years.

now lets talk about 24 drives spun down

I've been using sleep with my drives in my various system for decades now, including my current TrueNAS Scale systems. I just have set the spindown timer to 2 hours so as to prevent constant spindown/spinup cycles -- if 2 hours pass without activity, it typically means no one's at home or it's night time, so it's ok for the drives to go to sleep. With a 2 hour timer, there's enough activity during the day that the drives keep running and won't spindown needlessly.

it seems to me that turning on and off is always stressful for electronics, even for an ordinary lamp