On Wednesday 09 April 2008 21:18:35 Tvrtko A. Ursulin wrote:
quoted text
> I got one of them (WD5000AACS) recently and to my horror after less than
> three days of being power on this is what I saw:
>
> 9 Power_On_Hours       0x0032 100 100 000 Old_age Always  - 66
> 193 Load_Cycle_Count 0x0032 197 197 000 Old_age  Always  - 10233
>
> At this rate the disk would reach it's design limit for load/unload cycles
> in around 80 days. Not good - so I implemented a lame workaround of keeping
> disk busy every couple of seconds - hopefully that won't kill it sooner
> that unloads would..
>
> I am also currently talking with first line of WD's tech support trying to
> get some data on how exactly those drives manage head unloading, but that
> may not lead anywhere useful.

I got back from WD's tech support and received a DOS utility which can control 
this drive feature, apparently using vendor specific commands. With it head 
unload timer can be disabled or set to a period between 100ms and 25.5s. 

Of course I asked for more than a DOS utility, but the question really is how 
was this feature intended to work with Windows for example, is there 
something there which would prevent such rapid load/unload cycle growth, and 
why isn't it documented somewhere?

I am kind off hoping that someone from WD is reading this list and will notice 
this in case my effort with tech support fails.

Tvrtko
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