On Sat, 8 Mar 2014 11:41:09 -0800 (PST), wrote:

On Saturday, March 8, 2014 1:47:14 PM UTC, Harry Bloomfield wrote:

Some long while ago, I bought a Buffalo USB 1Tb hard drive. It is
physically quite large and came with its own wall-wart PSU. I have not
really used it much. This week my ISP sent me a new router, which
included a USB Samba connection and I have now managed too get the
drive working via that.
If unused for a while, the hard drives in my PC power themselves down,
so I rather expected there might be some way to achieve that with the
Buffalo drive. It seems silly to have it running continuously if it is
not being used, but where the router and Buffalo are located, is not
easily accessed and some way away. Is there some way too set such a
drive too self power down after a period of inactivity please?

If there isnt one, you could plug it into a pc. ISTR unmounting spins them down.


I've noticed that spin down effect on USB drives when they're
unmounted. Slightly annoying for me is that this doesn't happen with
e-SATA connected drives.

It's quite possible that the Buffalo USB drive is already set to spin
down after a 10 or 15 minute timeout period (guaranteed to in fact if
they've used a Seagate Special).

The spin down of the internal drives in the PC will be mediated by
the power management features of the OS rather than the built in 1 to
15 minute programmable timeout that can be enabled in the HDD's own
controller.

The power management will simply issue a "Standby_Immediate" AT
command to the drive at timeout. Incidently the same AT command that
an SSD aware OS is _supposed_ to issue just prior to switch off when
shutting down.

The choice of using spin down power saving could be described as a
case of: a "Damned if you do. Damned if you don't." choice. What's
best depends on whether you value the electricity savings over the
integrity of your data which rather depends on your usage pattern.

If you're likely to only be working the drive just once or twice a
week for an hour or two's worth of intense activity each time, the
spin down power saving benefit outweighs the risk of disk failure due
to startup stresses and the effects of thermal cycling. In this case,
I'd be inclined to set a longish timeout period of an hour or three.

If you're going to be making frequent accesses in relatively short
bursts of activity throughout each working day, you'd be well advised
to disable power saving spin down (if you can - you won't have any
choice in the matter if the drive is a Seagate Special) or else set it
to a 3 or 4 hours timeout period so that it's only effectively spun
down once a day to give it an 'overnight rest'.

In essence, you're trying to avoid cycling the drive temperature up
and down more than 3 or 4 times a day. If you've any doubts over this
(and you value your data more than the 5 or 6 quid saving per drive on
the annual electricity bill), imo, you'd best disable spin down
altogether (discretion being the best part of valour in this case).

However, as I've mentioned twice already, you may have no choice in
the matter.
--
Regards, J B Good