[mythtvnz] HDD Load Cycle Count ticking over too fast [SOLVED (sort of)]

[Mike Brady]

Quoting Stephen Worthington <stephen_agent at jsw.gen.nz>:

> On Thu, 28 Jun 2012 12:16:25 +1200, you wrote:
>
>> Well it's official. I really am very thick. I just could not understand
>> why a non-system drive should have constant disk access when it is
>> completely idle. So I used iotop to see what was happening and sure
>> enough nothing was touching the drive. Then the penny finally dropped.
>> Of course. It's bleeding obvious. Every time you run smartctl you wake
>> up the drive so if it's parked the LCC increments by one. So by checking
>> the LCC every 15s I was causing it to increment every 15s because the WD
>> green drives intellipark every 8s.
>>
>> So now the only question is whether typical usage of the disk will cause
>> excessive load cycles. From smartctl stats it seems not. I calculate it
>> will take about 12 years to reach 300,000 cycles based on past usage. So
>> nothing to worry about after all.
>>
>> BTW observing that the interval between disk I/O on my system drive
>> (WD10EADS-00L5B1) is frequently more than 8s but the LCC count is low on
>> this drive I must have lucked out with the firmware (01.01A01) on the
>> drive, i.e., it doesn't intellipark every 8s.
>
> I think the older drives use a longer timeout, 15-20 seconds or so.  I
> remember reading something like that when I was researching my
> problems.
>
> I would have thought that smartctl accessing the SMART data would not
> wake up a drive - I wonder why it does.  It seems a very bad idea that
> it should.  So maybe it is a bug in the firmware?  Or smartctl?  Or
> the SATA drivers?
>
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