[mythtvnz] HDD Load Cycle Count ticking over too fast

[Stephen Worthington]

On Mon, 25 Jun 2012 22:02:43 +1200, you wrote:

>Aargh! After my recent disk problem I decided to delve into smartmon 
>again. First thing I noticed was one drive had much higher 193 
>Load_Cycle_Count value than the other, older drive. So started watching 
>it and it ticks up every 30s or so IF the system is idle. Just watched 
>and recorded from the same disk and during this time the count didn't 
>increase which makes sense since it was busy writing/reading 100% of the 
>time.
>
>The old drive, which has the OS on it, has sat at the same load cycle 
>count during this time.
>
>This is the problem drive:
>Device Model:     WDC WD20EARS-00MVWB0
>
>ID# ATTRIBUTE_NAME          FLAG     VALUE WORST THRESH TYPE 
>UPDATED  WHEN_FAILED RAW_VALUE
>   4 Start_Stop_Count        0x0032   100   100   000    Old_age 
>Always       -       725
>   9 Power_On_Hours          0x0032   095   095   000    Old_age 
>Always       -       4206
>  12 Power_Cycle_Count       0x0032   100   100   000    Old_age 
>Always       -       723
>193 Load_Cycle_Count        0x0032   193   193   000    Old_age   Always 
>       -       23963
>194 Temperature_Celsius     0x0022   117   109   000    Old_age   Always 
>       -       33
>
>
>Older drive:
>Device Model:     WDC WD10EADS-00L5B1
>
>Vendor Specific SMART Attributes with Thresholds:
>ID# ATTRIBUTE_NAME          FLAG     VALUE WORST THRESH TYPE 
>UPDATED  WHEN_FAILED RAW_VALUE
>   4 Start_Stop_Count        0x0032   098   098   000    Old_age 
>Always       -       2961
>   9 Power_On_Hours          0x0032   085   085   000    Old_age 
>Always       -       11487
>  12 Power_Cycle_Count       0x0032   099   099   000    Old_age 
>Always       -       1219
>193 Load_Cycle_Count        0x0032   200   200   000    Old_age   Always 
>       -       2961
>194 Temperature_Celsius     0x0022   116   109   000    Old_age   Always 
>       -       34
>
>You can see how the load cycle count relative to other counts is much 
>different between the two. Both are WD Green drives. The older one has 
>the OS on an EXT4 partition plus an NTFS partition while the newer one 
>has a single JFS partition.
>
>Any ideas about whether it's the file system (JFS vs EXT4) or OS setting 
>or BIOS or HDD firmware that's causing the problem? I can't grasp why 
>the disk should spin down, park, then spin up again when it's idle. I'm 
>99% sure there should be no activity on the drive unless myth is 
>recording or playing.
>
>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.

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.

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.