Similar findings here, where the first batch of drives in our hadoop
clusters were WD greens. smartctl shows huge Load_Cycle_Count numbers
for those drives which have been in service for a while (and they do
indeed keep us busy with RMAs). Eventually we found this utility which
can disable the absurdly short head-park timer from within linux:

http://idle3-tools.sourceforge.net/

which might help, but I wouldn't choose to buy these drives again for
this purpose.

Graham

On Thu, Oct 04, 2012 at 11:07:03AM -0600, Doug Johnson wrote:
> Greetings,
> 
> I have built many RAID systems using desktop disks and they are
> generally quite stable. One of the issues with WD drives are with their
> Green drives. By default, they park the heads after ~8 seconds of
> inactivity. This will cause them to drop out of the array. The disk
> firmware can be configured to disable this feature. I have had very good
> luck with Samsung and Seagate drives. I have never spent the money on
> Enterprise level drives.
> 
> BTW: The head parking feature is notoriously bad. If you calculate 1
> park every 8 seconds. At constant usage, the drive will die in about 3
> months. Perhaps this feature is fine for a desktop, but it is not for a
> server or production environment.
-- 
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Graham Allan - I.T. Manager - [log in to unmask] - (612) 624-5040
School of Physics and Astronomy - University of Minnesota
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