Marco, > Date: Sat, 26 Jan 2013 16:21:28 +0100 (CET) > From: bodr...@mail.dm.unipi.it > > Ciao, > > Il Sab, 26 Gennaio 2013 4:01 pm, bodr...@mail.dm.unipi.it ha scritto: > > I mean, which timing do you obtain with the following? > > ./speed -s $((1000000+775660)/2) mpn_mul_n mpn_mul_n > > Sorry... I mean: > > ./speed -s $[(1000000+775660)/2] mpn_mul_n mpn_mul_n
here is another example: frite% ./speed -s 600000 mpn_mul.1000000 mpn_mul.1000000 mpn_mul.1000000 overhead 0.000000002 secs, precision 10000 units of 3.33e-10 secs, CPU freq 3000.00 MHz mpn_mul.1000000 mpn_mul.1000000 mpn_mul.1000000 600000 #0.716044000 0.720045000 0.716045000 frite% ./speed -s 800000 mpn_mul_n mpn_mul_n mpn_mul_n overhead 0.000000002 secs, precision 10000 units of 3.33e-10 secs, CPU freq 3000.00 MHz mpn_mul_n mpn_mul_n mpn_mul_n 800000 0.676042000 0.680043000 #0.672042000 In the FTT range, multiplying n limbs by m limbs should not be more expensive then multiplying two numbers of (n+m)/2 limbs. In that case, we get a 6.5% slowdown with respect to that strategy. Note that I did not try to get the largest possible slowdown. Paul _______________________________________________ gmp-devel mailing list gmp-devel@gmplib.org http://gmplib.org/mailman/listinfo/gmp-devel