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

[Stephen Worthington]

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?