What are your feelings on Spin down?

 

In my experience a drive that stays running stays running; I have had drives run continuously for 8 years!  Conversely, I have replaced a lot of drives in machines for people who shut them down.

 

My logic is this; the load on the spindle motor and its control circuit is greatest during spin up; far more than spinning in idle.  This increased load repeated over and over again wears the motor and or circuit out quicker IMHO.  When running 24/7 the bearings on the other hand never get a break; which honestly I can't say I have ever seen be the demise of a drive other than being so loud I just retire it.  I have on the other hand, thrown out a lot of drives due to the click of death which I usually attribute to the motor circuit having failed.

 

The other big issue for people is power consumption.  I imagine this can vary greatly based on the number of drives and the drives themselves.  In my situation I use 6 WD green drives that have a quite low power draw; 2.5 watt at idle I believe.  The question is what are you really saving?  The spin up power consumption of most drives is 12 to 14 watts vs. the idle consumption of 3 to 6 watts.  So, basically if you end up spinning up drives all of the time you could be costing yourself more money <== Ok, maybe a little over stated   But in my mind the math just is not there for significant power savings when accounting for increased spin up load and the fact that we are talking a few watts per drive.  For me, 20 watts is a drop in the bucket compared to my overall power consumption.  Sure if you’re running 22 WD Blacks it could add up but you would be the exception.

 

Another area of concern is heat.  In my opinion if you have heat issues, spin down is not the solution.  If you base your cooling situation on drives that are spun down… what happens if the all spin up?  In my opinion a properly executed cooling system should eliminate any of these concerns.  I live in Minnesota and my server is in the basement… at the moment 16°C drive temps at idle are a bit on the low side

 

Last, is the wait time for spin up which there is not much to say, it sucks.  Sure you can adjust directory caching and whatnot but still... you have to wait sometime.

 

So, what are your opinions and experiences?  What do you think is worse for a drive.. running 24/7 idle or spin up/down cycles.

 

 

I have all WD Green drives and let my drives spin down. I think I have it set to spin down after an hour. Of coruse I can't remember if thats the default for unRAID or if I set it to that.

 

I'm just like you. I've had drives spin for years on end and never had a problem. What I have had a problem with is that one morning when you turn your machine on and hear the "click, click, click" and know its the drive telling you I'm done. At least unRAID has protection for that so my worries on that are way low.

 

However do I want all my currently installed drives spining all the time? Well no honestly. So I guess its just a matter of how long after they spin up do you want them to run. I use my machine every night for one reason or another, but then the rest of the day 18hours it just sits there until I get home.

 

I have plenty of fans in my case and I'm not worried about heat running, doing a parity check or off.

I tend to agree with you that spinning down drives after a short period of time is not a good idea.  Some people have it going every 15 minutes!  But I do set a spin down timer of 5 hours.  That means that normally a drive will spin up at most once a day.  

 

I have never kept my computers running 24x7, except PVRs.  And I have had a number of drive failures in PVRs.  The computers in my house run for the evening hours and are shut down overnight and most of the day.

 

Many of my array disks spin up once a month - for their parity check.  I have to believe it is better to have them spun down than run continuously.

 

BTW, if you just want to know if people have a spindown timer or not, you might want to limit the poll questions to that.  I have a spin down timer yet not trying to save every penney and I do believe that excessive spinup/down is bad for the drives.  Since I disagree with 2 out of the 3 parts of the yes response, I don't feel I can say yes.  And since I do have a spindown timer I can't say no.  So I just didn't answer.

I think I might change my timers too. I figure when I do use my PC there is a 4-5 or so hour window and no sense in having them turn on/off when they could just stay on for that period.

The question is what are you really saving?  The spin up power consumption of most drives is 12 to 14 watts vs. the idle consumption of 3 to 6 watts.  So, basically if you end up spinning up drives all of the time you could be costing yourself more money.

 

Energy is not power. Energy = Power x Time. Using easy numbers for an example, if spin-up uses 12 watts and takes say 5 seconds, and idle consumes 3 watts, then unless you're spinning down/up every 20 seconds or so you will save far more energy (= electricity cost) by spinning down when a disk is not in use.

 

Leaving the drive continuously running has got to be bad for the drive (and the wallet, environment, etc.), but so has spinning down/up excessively. There is a happy medium somewhere in between the two extremes, and I guess that "medium" (1 hour, 5 hour,...) depends on your server usage. If frequent disk activity is the norm then a several hour spin-down setting would probably work best. For low-power freaks like me who only ever write or read a single large blu-ray file once a day then 15 minutes should be ok.

 

That's my take on it. Happy to be corrected.

 

 

I think PVR's are much different than a drive spinning in idle.  PVR drives are hammered away at 24/7 and the armature is likely the failing component in 9 out of 10 drives.  I probably should have worded it better or provided another option, I will edit it slightly. 

 

@Hanabi - Not to get down to brass tacks but the spin up time for most 2tb drives is closer to 12 seconds according to many manufacturer specs; which seems to be longer than what it actually is. I would like to konw what the drives power requirements are when spun down.  Regardless, you are correct, I over stated it for theatrics but still... when you factor the difference in and the low power requrement at idle for most drives power savings is pretty insignificant overall.

 

So far I cant believe I am the only one that does not spin down.. this really surprises me.

 

The question I really wanted to pose was; what is worse for a drive, running all of the time or spinning up and down cycles.

I spin down because I would rather save power since it's only being used for 3-4 hours a day

 

no sense spinning the drives if they have no chance of being used

So I used this calculator at http://www.electricity-usage.com/Electricity-Usage-Calculator.aspx

 

Device Name:  WD20EADS x 6

Wattage of Device:  20 watts - Higher than it actually is.  WD20EADS = 3 watt idle

Kilowatt Hour Cost: .08 cents 

Hours of use per day: 24 

 

Cost Per Hour:  $0.001660 

Cost Per Day: $0.039840 

Cost Per Week: $0.279 

Cost Per Month: $1.12 

Cost Per Year: $14.50 

 

Given that the drives will be in use at least some of the time over the course of a year... I can only save something less than $14 bucks in a whole year... yeah I am leaving spin down off!  I firmly believe a drive is better off always running vs spin up/down cycling.

I started off with a Acer H340 WHS.. had some issues and now I have a unRAID setup.  I keep the WHS running all the time for backups and movies I plan to watch soon.  I keep my unRAID as long term archive and monthly backups but have the drives spin down after 2 hours, the WHS typically gets usually everyday but the unRAID is maybe a few times a week.  So I guess spin-down also depends on your usage pattern... if I had a daily spin up -- I would just keep them all spun up. 

 

I wonder if a group policy for spin down would be of benefit? spin down the least used ones and keep the frequently accessed ones up.

 

So I used this calculator at http://www.electricity-usage.com/Electricity-Usage-Calculator.aspx

 

Device Name:  WD20EADS x 6

Wattage of Device:  20 watts - Higher than it actually is.  WD20EADS = 3 watt idle

Kilowatt Hour Cost: .08 cents   

Hours of use per day: 24 

 

Cost Per Hour:  $0.001660 

Cost Per Day: $0.039840 

Cost Per Week: $0.279 

Cost Per Month: $1.12 

Cost Per Year: $14.50 

 

Given that the drives will be in use at least some of the time over the course of a year... I can only save something less than $14 bucks in a whole year... yeah I am leaving spin down off!  I firmly believe a drive is better off always running vs spin up/down cycling.

 

I think you're in the minority here, according to the poll numbers.

 

But that doesn't mean you are wrong.

 

Running drives have an advantage of lower temperature variations and fewer start ups and stops, which are definitely stressful activities.

 

Would be interested if there are any studies along this line, or manufacturers recommendations.

 

Like many, I'm in between on this one.  I wouldn't say that infrequent spin ups / downs is harder on the drives, but again, the key here is infrequent.  I like the 5-7 hour window for myself due to always using my server when I'm home in the evenings.  I would agree with you that a frequent (1 hour or less) spin down schedule if harder. 

 

I too have had a good bit of experience in running drives without spinning down 24/7 for years.  My choice for this in the past has been mainly for my own personal convenience of saving 15 seconds here and there.  The cost savings is so minimal to me that its worth a little extra to not wait (like waiting 10 mins in line at a gas station when the one across the street has no line, but is 5 cents more.  I choose the no line for 5 cents more.).

 

I began with unRAID thinking there is no need to let the drives spin down, but changed it to the 5-7 hour window since that tends to be my evening watching times.  However, now that I have installed Sick Beard on the server, my spin up / down times have changed to the Sick Beard schedule, so I'm giving thought to having them stay spun up at all times again.

I'm with kizer.  I think my drives spin down after an hour or so but I only use my server for 4-5 hours a day max.  I'm going to change my timers to be 5 hours and let the disks spin while the server is running and I'm either copying files or streaming.

So there was a study done by the google and its quite interesting stuff.  By their own admission the data is just not there on power cycles because most of their hardware is running 24/7.  Nevertheless it is really interesting; especially the temperature data.  It has prompted me to bring my server from the basement and slow down my fans!  Turns out cooler is NOT better, in fact its much worse!  Hot is also not good but it seems to be much less of a factor.  35-40 seems to be the sweet spot.

 

labs.google.com/papers/disk_failures.pdf

That report has been discussed here extensively.

Lol... I just posted it again in the General Support forum.  You can delete it if you like.  I did a search and didnt find anything

I'm with kizer.  I think my drives spin down after an hour or so but I only use my server for 4-5 hours a day max.  I'm going to change my timers to be 5 hours and let the disks spin while the server is running and I'm either copying files or streaming.

You only use the server for 4-5 hours a day.

So I have a question : is powering down the server not a better saving power solution ?

 

I do use my unRAID for media server almost exclusively (and some backup occasionnaly).

And like you that is 4-5 hours a day.

So when I sleep or work, I don't need it. It is sleeping.

I believe it save more power/energy in this state then just spinning down the HD and leaving the server on.

Would be interested if there are any studies along this line, or manufacturers recommendations.

maybe there is some interesting info here

http://storagemojo.com/2007/02/19/googles-disk-failure-experience/

 

EDIT:

oh i see some one else posted already about googles results

You only use the server for 4-5 hours a day.

So I have a question : is powering down the server not a better saving power solution ?

 

I do use my unRAID for media server almost exclusively (and some backup occasionnaly).

And like you that is 4-5 hours a day.

So when I sleep or work, I don't need it. It is sleeping.

I believe it save more power/energy in this state then just spinning down the HD and leaving the server on.

 

Yes, what I meant was that while my server is on those 4-5 hrs per day, I will keep all drives spinning rather than have them spin down after a half hour or an hour.

I think it also depends on how many drives you have in your server(s). There's no way I'm leaving 36 hard drives spinning all day.

That was one of the reasons I went with unRAID.

 

I leave two drives spinning 24/7, the two in my two single-drive Buffalo NAS devices -- those devices consume 9W and 12W respectively.