On Wed, Dec 22, 2010 at 10:42 PM, david wrote:
I own 8 of the WD 1TB Green drives along with 5 WD 500GB RAID Edition
drives so I've seen this stuff up close over the last year..
A couple of points for consideration:
1) The Green drives do typically run at lower RPM. It's part of the
power saving strategy. I don't typically thing drive RPM has a huge
impact on audio work but clearly others could have a differing opinion
on that. It would make for an interesting conversation I think.
2) The biggest part of power saving on the WD Green drives is that
they park the heads _very_ often. While this hasn't been a big problem
under Windows for me under Linux it's a bit of an unknown at this
point. I have one system that uses one of the 1TB drives as the main
system drive. The head gets parked and then Linux wakes it up every 2
minutes or so. The issue is these drives are only spec'ed at 300,000
head parks over their lifetime and then they are out of spec.
30 parks per minute * 24 hours * 365 days = 262,800 head parks.
Basically, if the drive is left in a Linux system that's powered up
all the time then the drive is out of spec in a little over a year.
Does this matter? I don't know. I have one machine that is a year old
and it's approaching end-of-life?
3) One of the potential advantage I see with the larger density drives
is they are using 4K sector sizes instead of 512 byte. As long as you
partition on a 4K sector you only need to do one read of the drive to
get 4K vs 8 reads with older 512 byte drives. In my mind that's a big
potential win in terms of real speed independent of what the RPM of
the drive might be. For audio data where you have long streams of data
you aren't going to waste much disk space.
Please note that last time I looked the 4K drives don't identify them
selves as such so you have to know how to do the partitioning
correctly up front, keeping everything on a 4K boundary by hand. If
you don't these drives become __VERY, VERY, VERY__ slow.
Hope this helps,
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