[PD] Super computer made of legos and Raspberry Pi computers

[Charles Henry]

On Mon, Sep 17, 2012 at 4:11 AM, Andy Farnell
<padawan12 at obiwannabe.co.uk> wrote:
>
> Hearing it from the front line is really interesting Chuck. I am
> a little envious at the excitement a project like that must
> produce.
>
> Do you know of Joe Deken and the "suitcase supercomputer"
> project? He is a big Pd proponent (and friend of Miller I believe)
> and they are also looking at R-Pi boards for their next
> portable cluster (I'm probably telling you stuff you already
> know)
>
> best
> Andy

Actually, I just read the post yesterday from Joe--I was sort of aware
of the San Diego Supercomputing Center before now.
The RPi boards are interesting, and since the best you can do is
100Mb/s, the switch gear should be relatively cheap (and old).

However, if you can consolidate your systems more, you need fewer
cables, smaller switches, etc...

So--look forward to the Kontron KTT30 board which hosts the Tegra 3
SoC.  There's no word yet on the price, but it's about 4x as powerful
as a Raspberry Pi.  So, if it comes in low enough (say $120-140, then
it just might beat the RPi for cost.


>
>
>
> On Sun, Sep 16, 2012 at 10:26:56PM -0500, Charles Henry wrote:
>> On Sun, Sep 16, 2012 at 3:26 PM, Andy Farnell
>> <padawan12 at obiwannabe.co.uk> wrote:
>> > On Sun, Sep 16, 2012 at 10:24:45AM -0300, Alexandre Torres Porres wrote:
>> >> now my question is;
>> >>
>> >> spending 4k to build a Pi supercomputer can give you more power and
>> >> possibilities than with a top of the line MAC for example (which will cost
>> >> just as much, and be a quad core 2.7 intel i7, 1.6GHz bus, 16GB Ram).
>> >
>> >
>> > We keep using the word 'supercomputer', and maybe a bit of
>> > perspective would help clarify matters of scale.
>> ...
>>
>> > A supercomputer is, by definition, that which is on the cutting edge of
>> > feasible research. Most supercomputers are in a single location and not
>> > distributed or opportunistic, they usually have a building dedicated to
>> > them and a power supply suitable for a small town of a thousand homes
>> > (a few MW). A team of full time staff are needed to run them. They cost a
>> > few hundred million to build and a few tens of millions per year to operate.
>> > Current supercomputers are measured in tens of Peta FLOPS, ten to a hundred
>> > times more powerful than the equivalent mainframe, and are primarily
>> > used for scientific modelling.
>>
>> Yeah, but when I tell people what I do, do you think I say "cluster
>> computing" or symmetric multiprocessing or CUDA applications engineer?
>>  No, I tell them I work with "supercomputers"--It's not a term for
>> practitioners, since there's more specific things to say, ... and it
>> keeps people from thinking I'm going to waste time talking about nerdy
>> shit that I don't want to talk about anyway :)
>>
>> > The current guise of the 'mainframe' is what we would now see as a
>> > Data Center, a floor of an industrial unit, probably much like
>> > your ISP or hosting company with many rows of racked indepenedent
>> > units that can be linked into various cluster configurations
>> > for virtual services, network presence and data storage.
>> > Aggregate CPU power in the region of 10 TFLOP to 0.5 PFLOP
>>
>> At the moment, I'm (the engineer) putting together the proposal for a
>> grant for GPU computing resources (for the researchers and
>> scientists).  We're looking to spend about $750,000 on hardware that
>> will perform about 100 TFLOPS.  Mostly it will be made up of--whatever
>> NVIDIA Tesla is most cost/power effective--in servers that will hold 4
>> GPUs.  Altogether, we hope this fills up 5-10 racks (in our shiny new
>> energy efficient data center with 32 racks, that the f'ing fire
>> marshall won't let us into for another month, when we've been
>> postponed since June anyway).
>>
>> > Supercomputers are still supercomputers, by definition they are
>> > beyond wildest imagination and schoolboy fantasies unless
>> > you happen to be a scientist who gets to work with them.
>> > A bunch of lego bricks networked together does not give you 20PFLOP,
>> > so it does not a supercomputer make.
>> >
>> > However, there is a different point of view emerging since the mid
>> > 1990s based on concentrated versus distributed models. Since the
>> > clustering of cheap and power efficient microcomputers is now
>> > possible because of operating system and networking advances,
>> > we often hear of amazing feats of collective CPU power obtained
>> > by hooking together old Xboxes with GPUs, (Beowulf - TFLOP range)
>> > or using opportunistic distributed networks to get amazing power
>> > out of unused cycles (eg SETI at home/BOINC and other volunteer
>> > arrays, or 'botnets' used by crackers) (tens to hundreds of TFLOPS).
>>
>> Clustering is currently the most scalable model for supercomputers.
>> Many expensive options exist for systems with large numbers of cores
>> and shared memory--but year after year, more circuits get put on a
>> single die.  Generally when you think of supercomputers these days,
>> it's a network of systems that each have a lot of x86_64 cores and a
>> maybe nice co-processor (like the NVIDIA Tesla's).
>>
>> Some of the IBM machines (and Cray, still?) use pipelined multi-core
>> processors of a different architecture and 1000s of cores on a single
>> system, but I don't see that as a trend that will survive.
>>
>> Chuck