Western Digital Rant

Jim Cockfield wrote:

What Operating System are you using?

WD Green Drives (and laptop Blue drives for that matter) are designed to park the heads quickly after an inactivity period.

That behavior is controlled by the drive firmware, independent of any power saving setting features in a PCs BIOS or Operating System.

With some Operating System configurations, it can cause issues. Basically, most of the WD Green drives will park the heads after about 8 seconds of inactivity. But, if you have an operating system that's trying to access the drive around every 30 seconds (as many Linux installs or NAS installs will do), then you end up with a constant parking/unparking of the drive heads with WD Green Drives.

Most of the desktop Green Drives are rated for 300,000 load cycles, and I've seen that much in around 6 months of typical use with desktop linux distros. Here's one post I made on the subject a while back, where a WD Green Drive racked up over 220,000 load cycles in around 4 months:

http://forums.dpreview.com/forums/post/39173922

BTW, that specific drive is now retired (after I started seeing sector read errors). I just used ddrescue (a linux utility designed to copy a failing drive) to move the contents to a new drive and put it on a shelf, as the load cycle count had already exceeded the maximum allowed and the drive was beginning to fail on me.

Interestingly, the new drive I copied the data to (a WD 1.5TB Green Model) has already racked up over 89,000 load cycles in 4 months of use. That's better than the last one. But, I suspect that's because of my usage pattern, where I'm running BOINC (Berkeley Open Interface for Network Computing) software on it that's accessing the drive more often, keeping the constant parking/unparking of the drive heads at a lower rate.

But, I suspect it will exceed the maximum load cycle rating in around 1.5 years, despite my current usage pattern that seems to result in less parking/unparking of the drive heads.

A Scorpio Blue Drive in my wife's laptop also had the same symptoms (excessive load cycle count when running Linux). It made it to around 3 Million Load Cycles before it started failing. But, the laptop WD Blue drives like that are rated at 600,000 load cycles (versus only 300,000 for the WD Green Desktop Drives). I can't complain too much about the laptop drive (given that it lasted a lot longer than I expected it to, given the excessive load cycle count).

Now, WD does have a DOS based utility you can boot into and tweak the firmware settings for the timeout values that some of the WD green drives use. But, the utility doesn't work on all of the WD Green models. Again, how the WD Green Drives handle parking of heads after an inactivity timeout is under firmware control, and is not something you can change via Operating System settings.

If you google for WD Green Drives and Load Cycle Count, you'll find loads of articles and post on the subject, where you can see drives exceeding their maximum rated load cycle count within a year in some cases.

That mostly happens with Linux based installations. But, you see some reports of Windows setups exhibiting the same type of behavior.

Anyway, bottom line is that WD is trying a bit too hard to save power, and that can cause issues with some setups (where you end up with a constant parking/unparking of the drive heads, which causes more wear on the head mechanism).

In any event, I think I'll probably avoid the WD Green Drives going forward because of their behavior in that area.

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JimC
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