in reply to Sorting IP addresses, lots of them, quickly

and faster... 

use Benchmark qw(cmpthese);

use Socket;
use Sort::Key qw(ukeysort keysort);

my $n = 1000000;

my @address = map { join ('.', map {int rand 256 } 0..3) } 0..$n;

print "\@address populated\n";

sub gloryhackish {
  my @in = @address;
  my @sorted = map { $_ = inet_ntoa($_) }
    (sort (map {$_ = inet_aton($_)} @in));
}

sub ks {
  my @sorted = keysort { inet_aton($_) } @address;
}

sub uks {
  my @sorted = ukeysort { /^(\d+)\.(\d+)\.(\d+)\.(\d+)$/;
                          ($1 << 24) + ($2 << 16) + ($3 << 8) + $4 } @
+address;
}

cmpthese -1, { gloryhackish => \&gloryhackish,
               keysort => \&ks,
               ukeysort => \&uks };

[download]
on my PC, the results for 1 million elements are: 
             s/iter gloryhackish      keysort     ukeysort
gloryhackish   24.4           --         -29%         -48%
keysort        17.2          42%           --         -26%
ukeysort       12.7          92%          35%           --

[download]

Replies are listed 'Best First'.
Re^2: Sorting IP addresses, lots of them, quickly
by gloryhack (Deacon) on May 16, 2007 at 10:36 UTC
    Ooh, I like it! ++ and then some!

    I had to install Sort::Key to give it a whirl, and I can't manage to get the same 92% number, but I still like it just fine. Here's what I get, best of three, with ST and GRT thrown into the mix: 

    @address populated
Benchmark: running gloryhackish, grt, ks, schwartzian, uks for at leas
+t 30 CPU seconds...
gloryhackish: 34 wallclock secs (33.28 usr +  0.19 sys = 33.47 CPU) @ 
+ 0.12/s (n=4)
       grt: 34 wallclock secs (34.62 usr +  0.06 sys = 34.68 CPU) @  0
+.12/s (n=4)
        ks: 34 wallclock secs (34.04 usr +  0.03 sys = 34.07 CPU) @  0
+.18/s (n=6)
schwartzian: 55 wallclock secs (54.62 usr +  0.11 sys = 54.73 CPU) @  
+0.04/s (n=2)
            (warning: too few iterations for a reliable count)
       uks: 36 wallclock secs (35.53 usr +  0.24 sys = 35.77 CPU) @  0
+.17/s (n=6)
             s/iter schwartzian         grt gloryhackish         uks  
+        ks
schwartzian    27.4          --        -68%         -69%        -78%  
+      -79%
grt            8.67        216%          --          -3%        -31%  
+      -35%
gloryhackish   8.37        227%          4%           --        -29%  
+      -32%
ukeysort       5.96        359%         45%          40%          --  
+       -5%
keysort        5.68        382%         53%          47%          5%  
+        --

    [download]

    Still, even at 47% I'm suitably impressed and will be using keysort. It strikes me as odd that in your results keysort was bested by ukeysort... hardware differences, perhaps? (Mine's an AMD64 X2 4400+ w/2G DDR2 RAM.)

    Thanks for pointing Sort::Key out to me!

    Edit: Running on my original list of 11818 addresses, gloryhackish comes in 31% faster than ukeysort but 47% slower than keysort. Hmmmm.... curious, but still convincing.

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[d/l]

In Section Cool Uses for Perl