[Wylug-discuss] Linux NAS advice.

[Will Newton]

On Mon, Jul 15, 2013 at 2:04 PM, Jim Jackson <jj at franjam.org.uk> wrote:
>
>> >> > A word of warning about RaspberryPi - Ethernet traffic AND external
>> >> > USB disk traffic SHARE a link from the USN/Ether chip to the ARM chip, and
>> >> > that link is HiSpeed USB 2. So if you are file serving, the data goes up
>> >> > this link from the disk to the cpu, then back down the link from cpu to
>> >> > ether. This link is a serious performance bottle neck. I'd search for
>> >> > RPI USB fileserving benchmarks before committing to using the RPI for
>> >> > anything other than trivial fileserving.
>> >>
>> >> Agreed. It's also a pretty bad USB host controller in the Broadcom
>> >> chip which pushes a lot of load onto the CPU. The core used is an
>> >> ARMv6 too which is not that well supported - for example Fedora are
>> >> switching to ARMv7 only and I expect other distros will follow suit in
>> >> coming months and years. A little extra money spent will get you a
>> >> much better board than Raspberry Pi.
>> >
>> > At least the Debain based Raspbian Distro will be available for the life of
>> > the RPI, and is customised for the ARMv6. From what I've seen so far you
>> > will need to pay out at least double - but if you know of cheaper I'd be
>> > interested.
>>
>> Raspbian appears to be a fully community supported distro so the level
>> of support may vary.
>
> No. It's debian Wheezy, rebuilt for the ARMv6 with some some extras
> specifically for the RPI HW supported by the Raspberry PI foundation. They
> are paying people to do specific work - like the RPI wayland
> implementation.

Ok, I am not familiar with it, I was just going from the rapsbian.org website:

"Raspbian is not affiliated with the Raspberry Pi Foundation."
"Raspbian is a community funded and supported free software effort."

>> A beagle bone black is about 2 quid more and is IMO a better choice.
>> I'm not sure how much a Cubieboard sets you back in pounds sterling
>> but maybe another 20 or 30 pounds.
>
> Have just checked it out and the base price seems to be $45, as opposed to
> $35. But it does seem to be a better design.

The prices I found on the Farnell element14 shop were:

Pi Model B: £28
Beagle Bone Black: £30

Although I didn't look into it very far, so there may be extra costs incurred.

> I found this page that gives a comparison...
>
>   http://roboteurs.com/beaglebone-black-vs-raspberry-pi/
>
> And I suppose the Ether/USB don't share a bottleneck? Shame it
> doesn't have SATA :-) Which it seems the Cubieboard2 has! Mmmm...

The BeagleBone ethernet connects via MII to the AM335X so in theory
should not have any impact on USB performance. It's not gigabit
ethernet, which would be ideal for a NAS, but then not many boards (if
any) in this price range seem to support that.