lots of load-cycles on WDC WD400UE-22HCT0

[Anton Ertl]

The last hard disk in my iBook caused some trouble, so I recently
replaced it with a 40GB 2.5" hard disk from WD (extracted from an
external USB drive).

Most of the time this new drive makes some noise (somewhat like a big
head movement) every thirty seconds (occasionally more often, at some
times very rarely). After looking at the SMART output (with smartctl
-a under Linux), I found that every time that noise occured, the
Load_Cycle_Count had increased by 1. So apparently the noise is a
load-cycle, whatever that may be.

Overall, in the 400 Power_On_Hours until now the drive has increased
the Load_Cycle_Count to 38265. The VALUE field for Load_Cycle_Count
has gone down to 188 (from (guess) 200). At this rate, the VALUE will
reach 0 (the threshold) in 6300 hours (less than a year, since I tend
to have it permanently on), and supposedly I should replace the hard
disk then. I would like to avoid that, because replacing the hard
disk of an iBook is a lot of work.

Also, the noise is somewhat annoying, especially if it makes me worry
about hard disk.

So, what are these load cycles about? Do they really wear down the
hard disk, as the reduction in the VALUE field indicates? Is there a
way to get the hard disk to perform them less frequently (after all,
sometimes it performs them much less frequently, but I don't see a
reason for these different behaviours)?

Technical data:

Device Model: WDC WD400UE-22HCT0
Serial Number: WD-WXE805363672
Firmware Version: 09.07D09

The temperature is currently reported as 41 degrees Celsius, but I
have also seen temperatures of 46 degrees.

Thanks in advance. Merry Christmas.

- anton

 

[Anton Ertl]

(e-mail address removed) (Anton Ertl) writes:
[38000 load cycles in 400h on a WD 40GB 2.5" disk]

With a little more searching I found

http://web.glandium.org/blog/?p=54

and it gave the following answers to some of my questions:

So, what are these load cycles about?

It's about parking the heads in a lifted position (unloading) to make
the hard disk more shock-proof. Unfortunately, for some reason the
head is unparked (loaded) immediately afterwards, so the whole thing
makes no sense.

Is there a
way to get the hard disk to perform them less frequently?

Under Linux "hdparm -B254 /dev/hda" works for my disk, but others have
had less luck.

- anton

 

[Arno Wagner]

The last hard disk in my iBook caused some trouble, so I recently
replaced it with a 40GB 2.5" hard disk from WD (extracted from an
external USB drive).

Most of the time this new drive makes some noise (somewhat like a big
head movement) every thirty seconds (occasionally more often, at some
times very rarely). After looking at the SMART output (with smartctl
-a under Linux), I found that every time that noise occured, the
Load_Cycle_Count had increased by 1. So apparently the noise is a
load-cycle, whatever that may be.

Overall, in the 400 Power_On_Hours until now the drive has increased
the Load_Cycle_Count to 38265. The VALUE field for Load_Cycle_Count
has gone down to 188 (from (guess) 200). At this rate, the VALUE will
reach 0 (the threshold) in 6300 hours (less than a year, since I tend
to have it permanently on), and supposedly I should replace the hard
disk then. I would like to avoid that, because replacing the hard
disk of an iBook is a lot of work.

Also, the noise is somewhat annoying, especially if it makes me worry
about hard disk.

So, what are these load cycles about? Do they really wear down the
hard disk, as the reduction in the VALUE field indicates?

Yes. One reason why notebook HDDs are usually specified for
500.000 of these, while desktop drives are only specified
for 50.000 or the like. I am guessing that "Load_Cycle_Count" is
similar to "Start_Stop_Count". 100 per hour is definitely too
many.

Is there a
way to get the hard disk to perform them less frequently (after all,
sometimes it performs them much less frequently, but I don't see a
reason for these different behaviours)?

Assuming you run MacOS or OS-X, I think it is not the disk that does
this. It is the system telling the disk. You should be able to change
this with some "power" or "powersave" options or the like. It should
give you an option to set the idle time until the disk spins down. Set
to something like 15 minutes or more and you should be fine. I am not
a MAC expert, so I don't know which control field will have this in
it.

Alternatively if this happens when you run Linux, then it may be the
disk. I have Linux on my laptop but there is no automatic spin-down
AFAIK. Under Linux it does not make sense anyways to stop the disk,
sincethese is a lot of activity and the disk is accessed all the
time. If it is the disk, WD should have some configuration utility.

Technical data:

Device Model: WDC WD400UE-22HCT0
Serial Number: WD-WXE805363672
Firmware Version: 09.07D09

The temperature is currently reported as 41 degrees Celsius, but I
have also seen temperatures of 46 degrees.

Should be ok for a notebook HDD.

Arno