[mythtv-users] Netbook as low-power combined back-end / front-end?

[Tyler T]

>> My headless BE is a SheevaPlug, a fanless 1.2Ghz 512MB ARM device
>
> <10 watts!  That's impressive!
>
> Do you have any stats on the loads the SheevaPlug runs at?   Is that
> 6-9 watts under load?

The Sheeva by itself idles at about 4W and runs full tilt about 6-7W.
A 2.5" HDD draws another 2-3W or thereabouts.

> Is it running high CPU loads all the time
> because it is underpowered?

The only time the CPU goes to 100% is when Myth does a scheduling run
(once a day or when I schedule a new recording). Recording takes 20%
per stream and playback ~10% or so if I remember right. (My
utilization is higher due to the USB HD, eSATA would be better.)
Otherwise, it idles like any other machine since I don't transcode or
commflag.

Note, this is with 0.23. Someone mentioned that 0.25 requires more CPU
on the BE but I have no hard numbers. I want to upgrade to 0.25 but as
usual, personal life interferes with geek projects! Maybe someone else
here has run 0.25 on ARM and can report.

> The SheevaPlug sounds cool, and being ARM wouldn't bother me

FYI there are other Sheeva-like devices that use the same Kirkwood
CPU, see: http://en.wikipedia.org/wiki/Sheevaplug

> I would have to
> figure out a better front-end if I went that route and used a split
> front/back system.

You could use your existing case and power supply and drop in a new
uATX mobo with a Sempron or Atom. (A while back there was a thread
here about the Sempron that suggested it was reasonably power
efficient.) Replacing the FE's spinning disk with a cheap USB
thumbdrive saves some juice too.

> If I used my current system as a front-end, even
> for just a few hours a day, it would negate a lot of the power
> savings.

True, but at some point there's a crossover where a power-hungry
machine that spends most of it's time off will actually have a lower
*average* power consumption than a power-sipping device that's on all
the time. So, it may pay to run the numbers on various scenarios.