> I have just bought a Samsung 2TB Story Station external USB 2.0 drive ...
> The disk works fine, except that it automatically spins down very
> quickly when it thinks it's not needed. Since it takes 5-10 seconds to spin
> up after doing a 'save' this has started to become irritating.
There are many "consumer" drives that do similar things now, unloading
the heads or even spinning the drive down in just a few seconds. I've
been dealing with Western Digital "Caviar Green" drives that unload
their heads every 15 seconds to save power and heat. This also wears
out the drive quickly; in the last year, my drive has used almost half
of its rated 300,000 "Head Load Cycles" visible in the SMART stats.
In the case of the WD drive, none of the things that WD recommends
actually works to fix it. (And most of them are ways to reconfigure
Linux daemons so they write less often to the drive, circumventing
rather than fixing the problem.) WD is deliberately hostile to Linux
systems, refusing to provide support for anything but Windows.
"hdparm -B 255 /dev/sde" supposedly turns off all power-saving
features. This command is what WD recommends using; however, their
drive rejects it with an I/O error.
My recommendation is that before buying a drive, you examine the
comments of other buyers, looking for this kind of issue. (I use
newegg.com, partly because they have extensive user-entered comments
on each product.) Reject any drive that has this problem. There are
many that don't. Give your business to companies and products that
build products that either don't spin down unreasonably -- or that
learn by noticing that after 100 spindown/spinup cycles over a couple
of minutes, there is no sense in spinning down again quickly.
This may be deliberate market segmentation by the drive vendors, akin
to charging 3x as much for the same drive with a SCSI interface.
People who don't want to wait every time they save a file -- or who
want their drive to last more than a couple of years -- may eventually
learn not to buy these very cheap drives that have this "poison pill"
embedded in their firmware.
If your vendor allows you to return drives for a refund or a credit
within 30 days, I recommend returning it, and telling them why.