github.com/remyoudompheng/bigfft@v0.0.0-20230129092748-24d4a6f8daec/README (about)

     1  This library is a toy proof-of-concept implementation of the
     2  well-known Schonhage-Strassen method for multiplying integers.
     3  It is not expected to have a real life usecase outside number
     4  theory computations, nor is it expected to be used in any production
     5  system.
     6  
     7  If you are using it in your project, you may want to carefully
     8  examine the actual requirement or problem you are trying to solve.
     9  
    10  # Comparison with the standard library and GMP
    11  
    12  Benchmarking math/big vs. bigfft
    13  
    14  Number size    old ns/op    new ns/op    delta
    15    1kb               1599         1640   +2.56%
    16   10kb              61533        62170   +1.04%
    17   50kb             833693       831051   -0.32%
    18  100kb            2567995      2693864   +4.90%
    19    1Mb          105237800     28446400  -72.97%
    20    5Mb         1272947000    168554600  -86.76%
    21   10Mb         3834354000    405120200  -89.43%
    22   20Mb        11514488000    845081600  -92.66%
    23   50Mb        49199945000   2893950000  -94.12%
    24  100Mb       147599836000   5921594000  -95.99%
    25  
    26  Benchmarking GMP vs bigfft
    27  
    28  Number size   GMP ns/op     Go ns/op    delta
    29    1kb                536         1500  +179.85%
    30   10kb              26669        50777  +90.40%
    31   50kb             252270       658534  +161.04%
    32  100kb             686813      2127534  +209.77%
    33    1Mb           12100000     22391830  +85.06%
    34    5Mb          111731843    133550600  +19.53%
    35   10Mb          212314000    318595800  +50.06%
    36   20Mb          490196000    671512800  +36.99%
    37   50Mb         1280000000   2451476000  +91.52%
    38  100Mb         2673000000   5228991000  +95.62%
    39  
    40  Benchmarks were run on a Core 2 Quad Q8200 (2.33GHz).
    41  FFT is enabled when input numbers are over 200kbits.
    42  
    43  Scanning large decimal number from strings.
    44  (math/big [n^2 complexity] vs bigfft [n^1.6 complexity], Core i5-4590)
    45  
    46  Digits    old ns/op      new ns/op      delta
    47  1e3            9995          10876     +8.81%
    48  1e4          175356         243806    +39.03%
    49  1e5         9427422        6780545    -28.08%
    50  1e6      1776707489      144867502    -91.85%
    51  2e6      6865499995      346540778    -94.95%
    52  5e6     42641034189     1069878799    -97.49%
    53  10e6   151975273589     2693328580    -98.23%
    54