[ExI] ibm takes on the commies

[Samantha Atkins]

On 02/15/2011 11:52 PM, Eugen Leitl wrote:
> On Tue, Feb 15, 2011 at 11:14:11PM -0800, spike wrote:
>>
>>
>> Computer hipsters explain this to me.  When they are claiming 10 petaflops,
>> they mean using a few tens of thousands of parallel processors, ja?  We
> A common gamer's graphics card can easily have a thousand or a couple
> thousand cores (mostly VLIW) and memory bandwidth from hell. Total node
> count could run into tens to hundreds thousands, so we're talking
> multiple megacores.

As you are probably aware those are not general purpose cores.  They 
cannot run arbitrary algorithms efficiently.
>> couldn't check one Mersenne prime per second with it or anything, ja?  It
>> would be the equivalent of 10 petaflops assuming we have a process that is
>> compatible with massive parallelism?  The article doesn't say how many
> Fortunately, every physical process (including cognition) is compatible
> with massive parallelism. Just parcel the problem over a 3d lattice/torus,
> exchange information where adjacent volumes interface through the high-speed
> interconnect.

There is no general parallelization strategy.  If there was then taking 
advantage of multiple cores maximally would be a solved problem.  It is 
anything but.
> Anyone who has written numerics for MPI recognizes the basic design
> pattern.
>

Not everything is reducible in ways that lead to those techniques being 
generally sufficient.

- s