Are my disks spinning down?

[nickd]

Hello,

I'm trying to use hdparm to spin down my two sata disks using:

[NeddySeagoon]

nickd,

Unless these are laptop drives spinning them down can drastically reduce their life.
The platter bearings are usually 'air bearings' or 'fluid bearings'. Thats two names for the same thing
There is metal to metal contact when the platter is at rest and its rotary motion pumps air into the bearing, so the two metal parts become separated by a cusion of air - hence the name.

The downside is that wear takes place with every start, until the surfaces separate. Drives are rated something like 30,000 starts, check your drive spec and work out what you are doing to its life expectancy.
Of course, if its only a short term investigaion, its not a problem.

Usual causes of systems running hot are restricted airflow caused by dirt and dust build up on fans and heatsinks.
You need physiscal access to check. lm_sensors and friends can detect total fain failure.

An operating disc drive is about 12W. Thats small compared to a loaded CPU, which is over 30W.
Where are your thermal sensors mounted?
You only know that the sensors are hot - not the complete machine. Typically there is a sensor fabricated as a part of the CPU. The CPU is hot if thats showing high and another inside the CPU socket. Again that tells you about the CPU.
Like I say, check for a clogged heatsink.
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.

[nickd]

NeddySeagoon,

Thanks for taking the time to give me such a full answer!

The reason for my machine's hot running is that I've crammed 3x250GB SATA disks into a little tiny case. http://www.antec.com/uk/productDetails.php?ProdID=00131
It's a home backup and AV file-server which does little when not connected to one of our laptops. I'm trying to keep the noise down as much as keeping things cool.

I've backed the CPU off to about 1GHz (it's 2GHz Athlon64, 'cos I'm too tight to spring for a mobile CPU) and the heat is pouring out of the box when the disks are spinning.

CPU temp is around 40C - though I should be able to get some numbers from the motherboard once I figure out how to do it. It seems that I won't be able to get the SATA disk stats for a while yet under Linux.

I've got two backup disks set up for RAID1, and a third for system and non-critical data.

So I guess I'd still like hdparm to report spin up/down so I can track just how often the disks do spin up. It might be as little as once or twice a week for the backup driver which could give me upwards of 280 years(!). As for the system disk, perhaps I'll go for a laptop drive?

Thanks again,


Nick.

[NeddySeagoon]

nickd,

To get SATA disc stats you need the libsata patch, if it not in the kernel yet, that allows ioctl passthrough.
I've seen it around but not tried it.
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.

[nickd]

Thanks,

Sorry to lapse into stupid, but how do I check the status of libsata in my kernel?

N.