taku2ro at gmail.com
Sun Oct 30 10:39:49 CET 2011
On Sat, 29 Oct 2011 10:03:41 +0200 (CEST)
Marc Glisse <marc.glisse at inria.fr> wrote:
> do you only compute the exponentiation of a single number? When you
> parallelize, the higher the level, the greater the gains, and computing
> the exponentiation of several numbers in parallel sounds like it would
> work best.
I compute the exponentiation of several number. But in my case
depending on the exponentiation of a number, that of other numbers
become unnecessary. Since computing the exponentiation takes very
long, so I thought concentrating all the cores into on the
exponentiation of a single number would be better.
> Some algorithms parallelize better than others, and the one currently in
> gmp wasn't written for that purpose. If I understand correctly, the FFT
> multiplication first computes the transform of each operand (you could try
> doing those 2 in parallel), then multiplies the 2 transforms componentwise
> (what you already parallelized) and eventually retransforms to get the
> result. If you are close to the FFT threshold, you could also try
> parallelizing the toom multiplications.
Parallelizing the transformation itself or Toom, I believe, causes
nested #omp parallel directives. Doesn't it have a bad effect on the
Kentaro Yamamoto <call at taku2ro.dyndns.tv>
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