On Wed, 21 Apr 2010, Bill Davidsen wrote:
I hear this said, but I don't have any data to back it up. Drive vendors aren't stupid, so if the parking feature is likely to cause premature failures under warranty, I would expect that the feature would not be there, or that the drive would be made more robust. Maybe I have too much faith in greed as a design goal, but I have to wonder if load cycles are as destructive as seems to be the assumption.
What I think people are worried about is that a drive might have X load/unload cycles in the data sheet (300k or 600k seem to be normal figures) and reaching this in 1-2 years of "normal" (according to the user who is running it 24/7) might be worrying (and understandably so).
Otoh these drives seem to be designed for desktop 8 hour per day use, so running them as a 24/7 fileserver under linux is not what they were designed for. I have no idea what will happen when the load/unload cycles goes over the data sheet number, but my guess is that it was put there for a reason.
I'd love to find some real data, anecdotal stories about older drives are not overly helpful. Clearly there is a trade-off between energy saving, response, and durability, I just don't have any data from a large population of new (green) drives.
My personal experience from the WD20EADS drives is that around 40% of them failed within the first year of operation. This is not from a large population of drives though and wasn't due to load/unload cycles. I had no problem getting them replaced under warranty, but I'm running RAID6 nowadays :P
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