Re: re motion 50 (Just to you...)
On 2013-09-18 11:08:11 +0100, David Lester wrote:
> Richard, Ulrich,
>
> Here's a sketch of an EDP algorithm for a modern-style supercomputer chip.
>
> Assumptions:
>
> (*) EDP is the main thing you are interested in.
>
> (*) we have 1024 cpus.
>
> Then the algorithm is:
>
> stage 1: read-in A[i] and B[i] into core [i]. If there are more than 1024 elements in A/B, then
> read-in A[i % 1024] and B[i % 1024] to core i.
[...]
If EDP is to be implemented by a P1788 system library and non-parallel
programming language like C or Fortran, such an algorithm could not
be used, because such libraries or programming languages work in a
sequential model, parallelism being controlled by the developer at
a higher level. That's also why more complex features like EDP should
be reserved for the developer or specific libraries, and possibly be
grouped in another standard.
--
Vincent Lefèvre <vincent@xxxxxxxxxx> - Web: <http://www.vinc17.net/>
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Work: CR INRIA - computer arithmetic / AriC project (LIP, ENS-Lyon)