Ciao Paul, Il Ven, 25 Gennaio 2013 9:24 pm, Zimmermann Paul ha scritto: > in GMP 5.1.0, a multiplication of n x m limbs for m < n can be slower than > a multiplication of n x n limbs. Compare for example the line starting
> mpn_mul.1000000 mpn_mul.1000000 > 775660 #0.740046000 0.744046000 > mpn_mul_n mpn_mul_n > 1000000 0.736046000 #0.728045000 Is the problem due to the unbalanced size of operands, or it depends on the fact that FFT is poorly tuned for very big sizes? I mean, which timing do you obtain with the following? ./speed -s $((1000000+775660)/2) mpn_mul_n mpn_mul_n Regards, m -- http://bodrato.it/papers/combinatorics.html _______________________________________________ gmp-devel mailing list gmp-devel@gmplib.org http://gmplib.org/mailman/listinfo/gmp-devel
