Re^2: Choosing the right sort (Or: WUDsamatter?)

[ikegami]

Just to clarify Pustular Postulant, the OP must have called the functions in a void or scalar context. sort is optimized to do nothing in that situation, so the functions naive and orcish return instantly. Read more for confirmation of Pustular Postulant's results and confirmation that running the sorts in scalar context give results similar to those of the OP.

my @unsorted = sort map { "foo$_.tla" } 0..999;

Benchmark::cmpthese(5000, {
   naive       => sub { my @a = naive       @unsorted; },
   orcish      => sub { my @a = orcish      @unsorted; },
   schwartzian => sub { my @a = schwartzian @unsorted; },
   guttros     => sub { my @a = guttros     @unsorted; },
});

gives me

              Rate       naive      orcish schwartzian     guttros
naive       48.3/s          --        -34%        -46%        -60%
orcish      73.1/s         51%          --        -19%        -40%
schwartzian 90.1/s         86%         23%          --        -26%
guttros      122/s        152%         67%         35%          --

while

my @unsorted = sort map { "foo$_.tla" } 0..999;

Benchmark::cmpthese(5000, {
   naive       => sub { scalar naive       @unsorted; },
   orcish      => sub { scalar orcish      @unsorted; },
   schwartzian => sub { scalar schwartzian @unsorted; },
   guttros     => sub { scalar guttros     @unsorted; },
});

gives me

            (warning: too few iterations for a reliable count)
            (warning: too few iterations for a reliable count)
                Rate schwartzian     guttros      orcish       naive
schwartzian    107/s          --        -26%       -100%       -100%
guttros        144/s         35%          --       -100%       -100%
orcish      106383/s      99666%      73834%          --         -0%
naive       106383/s      99666%      73834%          0%          --

That's why it's important to show one's work :)