Hi:
Paul Leyland wrote:
> Actually, we at Microsoft Research in Cambridge have seen similar effects
> when compiling and running FFTW code. Our discovery is that the alignment
> of FP data values is critical. Get it wrong, and performance can plummet.
> Unless you set the alignment explicitly, it will be wrong approximately half
> the time.
Your right, I gained a 35% performance only with doing a simple trick to
be sure there were a 8-bytes alignement. On the other hand, I made the
FFTW library using long double float type (with a 'awful' 10-bytes long)
and the performance was near 65% in comparison with double float type
performance.
| Guillermo Ballester Valor |
| [EMAIL PROTECTED] |
| c/ cordoba, 19 |
| 18151-Ogijares (Spain) |
| (Linux registered user 1171811) |
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