04-21-2008, 09:48 AM
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| Junior Member | | Join Date: Sep 2009
Posts: 0
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 Re: Recommended hard drive temperature
Previously Franc Zabkar wrote:
> On 20 Apr 2008 22:03:24 GMT, Arno Wagner put finger
> to keyboard and composed:
>>Previously Franc Zabkar wrote:
>>> On Sun, 20 Apr 2008 14:16:28 +0200, lars put finger
>>> to keyboard and composed:
>>
>>>>In short, time well spend reading.
>>>>http://www.pdl.cmu.edu/PDL-FTP/Failu...ast07_abs.html
>>
>>> This document appears to be a statistical analysis of HD failures. It
>>> doesn't attempt to delve into the technical reasons for failure. The
>>> only time it discusses temperature, or SMART, is in reference to the
>>> Google article in my OP.
>>
>>> Google's experience suggests to me that temperatures below about 35C
>>> result in greater failure rates, which is contrary to normal
>>> expectations. However, Arno appears to be saying that the lower temps
>>> may be a consequence of failure rather than a cause.
>>
>>Exactly. It is possible, but the paper does not give us enough
>>data to determine whether it is the case. Also it runns contrary
>>to all known reliability characteristics of semiconductors,
>>other electronics components and mechnanics.
>>
>>Arno
> What about fluid dynamics? Maybe there is an optimal temperature for
> the platter lubricant and/or air bearing.
Possibly. Many drives in the Google study should actually
be pre-fluid bearing, if I remember correctly when they became
mainstream. A part would be FDBs though and maybe there is some
increased vibration effect or the like at lower temperaturers.
Now what would be interesting is SMART status changes for the
drives that dies at lower temperatures, compard to those that
died at other temperatures. Also temperature vs. FDB percentace
would be of interesst and temperature vs. disk age would be too.
Also disk performance in the week before death vs. temperature
would be nice.
> I found this interesting Samsung patent whose inventors claim that
> "flying height drops significantly in humid conditions" and that this
> can be remedied "by increasing the temperature of the air flowing
> between a slider's air bearing surface and the rotating disk surface
> it accesses".
> Method and Apparatus Reducing Flying Height Drop in a Hard Disk Drive
> Under Humid Conditions:
> http://tinyurl.com/4s5brl
> http://www.freshpatents.com/Method-a...0070297085.php
Interesting, I will have a look at there references! Not relevant
for data-center operation, however, since humididy is also strictly
regulated in there.
Arno
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