[mythtvnz] HDD Load Cycle Count ticking over too fast

[David Moore]

On 26/06/12 04:52, Stephen Worthington wrote:
> On Mon, 25 Jun 2012 22:02:43 +1200, you wrote:
>
>> Aargh! After my recent disk problem I decided to delve into smartmon
...
>>
>> BTW the load cycle count went from 23963 to 23971 while writing this.
>
> This is a known problem.  The newer WD green drives have a very short
> idle time before they park the heads - about 8 seconds.  You need to
> get a copy of wdidle3_1_05.zip from the WD site and use it to set that
> parameter to a much bigger number:
>
>
> http://support.wdc.com/product/download.asp?groupid=609&sid=113&lang=en
>
> IIRC, the option to disable it completely does not work on some
> drives, like mine, and I had to just set it to a large number (255?).
> You need to boot DOS to use that utility.  Fortunately, I still have a
> floppy drive on my Windows PC and DOS boot floppies, but if you are
> not so fortunate, you can use a copy of Ultimate Boot CD:
>
>    http://www.ultimatebootcd.com/
>
> It has a copy of the WDIdle3 utility on it ready to use.
>
> When using the WDIdle3 utility, it is best to only have that drive
> plugged in, otherwise the utility can get confused and program the
> wrong drive, even non-WD drives.
>

I'm in two minds about WDIdle3. Probably won't try it until I run out of 
other options. Interesting comment on WD's web site at 
http://wdc.custhelp.com/app/answers/detail/a_id/5357. "The increase in 
load/unload cycles for a typical desktop user are within design margins 
(drive has been validated to 1 million load/unload cycles without 
issue)." Hmm. Really? 1 million cycles? Guaranteed? Could be pure sales 
bullish IMHO.

That page also has a bunch of useless stuff about logging. Fat lot of 
help that is when it's a non-system disk that's cycling.

My current thought is some sort of simple read/write script that runs 
constantly but is ioniced down so it doesn't affect myth 
recording/playback. Might even be something in myth python bindings that 
can be used to detect recording/playback activity and stop/suspend the 
dummy read/write.

> WARNING: Shut down that drive immediately and do not use it until you
> have done this fix.  All hard drives have a limited number of head
> load cycles they can do before they fail.  WD do not specify what that
> limit is for these drives, but it is likely to be less than 500,000,
> probably around 300,000.  Linux and Windows can get a drive to that
> limit in just a day or two, under the wrong conditions.
>

My drive is at least a year old and has only reached an LCC of 24,000 
but is ticking over every 15s now. I guess it hasn't been idle that 
much. Either playing/recording or turned off. OR maybe it's something 
new since I upgraded from myth 0.23 to 0.25 which would explain how a 
year old disk is only up to 24,000 LCC. I wonder if 0.25 is periodically 
polling/probing all storage disks?

> BTW This is not at all a Linux problem - I have had exactly the same
> thing using Vista.  And it is not limited to just WD green drives.
> Some of the other newer WD drives have the same timer, just not set to
> such a drastically short timeout.  But they can with slightly
> different timing conditions get into a situation where they are
> loading and unloading all the time too.  I have had it with a
> WD2001FASS 2 Tbyte Black drive.  That drive has a count of 299871 at
> present.

She'll be right mate. A million cycles according to the WD salesman! :)