To spin or not to spin what is best for drive life ?

[Simon Bingham]

I think my drives are starting to fail over 4/5 years of constant spinning. So I'm replacing the 1st of 4 This has got me thinking.

What is best for the drives lifetime, to spin constantly. or to shutdown when idle. ?

My NAS system is not constant use, this probably once a day at most. !! I think if I set the drives to spin down after say 90 mins of non use they
might only spin up 3 or 4 times a week.

I'm using the Western digital 4TB drives Red ones.

Just wondered if there was any proper data on this. One the effect of constant running VS stopping and starting.

 

[Samuel Tai]

I believe leaving them spinning is less risky. The bearings achieve a steady-state lubrication film. Whereas, if you let them spin down, the lubrication can clot when it cools. Also, the heads achieve a steady-state fly height due to the air boundary layer off the platter surfaces. This layer doesn't exist at spin-up, so the chance of a head crash is higher.

 

[subhuman]

I agree. My personal experience, which is anecdotal and statistically insignificant, is that the most common mode of HD failure is taking a perfectly functioning drive out of service, only to have it refuse to ever spin up again.

 

[John Doe]

good question

I red it i this forum several times, keep it spinning is the way top go. But i never saw some studies about this.

However my nas should be effective in terms of monetary values. so I did a calc
How much money do I safe if the HDDs are spinning down.

values:
HDD consumes 5w
HDD cost me 200USD
kw/h cost me 0,25 USD

->let it spinning for 17 years = the cost of a new HDD

Narratives:
power consumption cost of a 17 years long spinning HDD is the same cost of buying new.
so in case the HDD breaks down in 2 years because of spinning on and off is more costly then let it spinning and breaks in 4 years.

the only questionable thing: Is it really true, that spin on and off is causing damage to an HDD

 

[Heracles]

the only questionable thing: Is it really true, that spin on and off is causing damage to an HDD

Yes it is. So often drives are operational and a simple reboot kills it because it involved a spin down - spin up.

Also, in the forum, there are people who posted their HDD stats about that and you can see drives way beyond the treshold they were designed form things like multi-millions spin up and down when the drive was designed for few hundreds of thousands.

The best way to keep your drive alive is to keep them spinning.

 

[Simon Bingham]

good question

I red it i this forum several times, keep it spinning is the way top go. But i never saw some studies about this.

However my nas should be effective in terms of monetary values. so I did a calc
How much money do I safe if the HDDs are spinning down.

values:
HDD consumes 5w
HDD cost me 200USD
kw/h cost me 0,25 USD

->let it spinning for 17 years = the cost of a new HDD

Narratives:
power consumption cost of a 17 years long spinning HDD is the same cost of buying new.
so in case the HDD breaks down in 2 years because of spinning on and off is more costly then let it spinning and breaks in 4 years.

the only questionable thing: Is it really true, that spin on and off is causing damage to an HDD

its not really the power consuption but the reliabiltiy, My drive has lasted 5 years now it is dying, presumably the others will follow soon, if I have left that drive in a packet for 5 years and just got this out then presumably this would work.
so there must be a trade off. I wonder if anyone has done the maths of stopping and starting vs running constantly

 

[Samuel Tai]

The only large-scale study of disk life span I could find is this Google paper.

https://static.googleusercontent.com/media/research.google.com/en//archive/disk_failures.pdf

Power Cycles. The power cycles indicator counts the number of times a drive is powered up and down. In a server-class deployment, in which drives are powered continuously, we do not expect to reach high enough power cycle counts to see any effects on failure rates. Our results find that for drives aged up to two years, this is true, there is no significant correlation between failures and high power cycles count. But for drives 3 years and older, higher power cycle counts can increase the absolute failure rate by over 2%. We believe this is due more to our population mix than to aging effects. Moreover, this correlation could be the effect (not the cause) of troubled machines that require many repair iterations and thus many power cycles to be fixed.​

So there appears to be a slight correlation between failure rates and spin downs, especially for older drives.