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Re: [LUG] Raspberry Pi now 100% Open Source on the ARM side

 

On Wed, 24 Oct 2012, tom wrote:

On 24/10/12 15:49, Gordon Henderson wrote:
On Wed, 24 Oct 2012, tom wrote:

If you want a cool cluster try the http://www.kickstarter.com/projects/adapteva/parallella-a-supercomputer-for-everyone?ref=home_popular
I want one!

Hm. I don't particularly agree with their pitch... For example, over 20 years ago I was working with a company building what we now know as clusters.. It's not a new concept. Biggest one I helped build at the time: http://unicorn.drogon.net/cs2.gif That had 256 compute boards each with a dual processor sparc and 128MB of RAM...

https://projects.drogon.net/a-box-of-200-raspberry-pis/

10 years ago I worked with a company who developed a general purpose plug-in pci/pcie card - 96 cores on it - under 10 watts a chip (they put 2 on a single plug-in card) see http://www.clearspeed.com/

So the concept isn't new. Making it affordable and "open" is...

The problem then and now still is: How do you program the things? The question we were always asked went along the lines of: I have this 30 year old FORTRAN program - make it go faster with more data ...

Want to play with multi-cores on a chip today? Buy one of these: http://en.wikipedia.org/wiki/Parallax_Propeller

e.g. http://www.xgamestation.com/view_product.php?id=51

Gordon

The parallela is programmable in C/C++ so no need to learn a new language and last time I looked multicore stiff was pretty easy on C++ and most of the apps I'd like to run on it are in C/C++ and easy to mod for multiprocessor running with a compile switch.

Meikos CS2 20+ years ago was programmed in C/C++ as well as FORTRAN - each node ran solaris... That didn't make it easier to program. Their CS1 - Transputers and i860's also was programmed in C/FORTRAN - again, even with the tools, people them reall did not want to re-write their 30-year old "babys" that they'd nursed from PhD through all their working lives - that why the likes of CRAY, etc. got the advantage - compiler technology and processors highly optimised to recognising and executing the array/vector arithmetic..

Clearspeed donʼt give a price so you have to ask them - I tend not to bother with that approach - you spend more on salesman time than you do on product.

You can't buy them anyway - they are now sort of dormant...

Same problem there though - no-one wanted to re-write their code "make it go faster". So Clearspeed (and others) would write their own librarys to inteface to their hardware that then provided the standard stuff like blas libraries and so on.

It's always been the case that if you write natively you'll get fantastic performance and always been the case (from what I've seen first-hand) that no-one wants to write natively because it's generally too hard.


The parallax is pretty slow - about 1/10th the speed of one core of my cpu on this desktop.

You wanted parallel processing...

What I'm saying is that it's there now - and has been for decades. It's nothing new at all.

Gordon
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