#!/usr/bin/perl -w
use Benchmark;
timethese(100, {
  a => q{
    my %hash = (key1 => 3, key2 => 2, key3 => "test");
                # I used 10000 more for a large test set (omitted for brevity)
    @keys = sort {
      $hash{$b} cmp $hash{$a}
        ||
      length($b) cmp length($a)
        ||
      $b <=> $a
    } keys %hash
  },
  b => q{
    my %hash = (key1 => 3, key2 => 2, key3 => "test");
                # I used the same 10000 more as above
    @keys =
      map  { $_->[0] }
      sort {
        $b->[1] cmp $a->[1]
          ||
        $b->[2] <=> $a->[2]
          ||
        $b->[0] cmp $a->[0]
      }
      map{ [$_, $hash{$_}, length $_] }
      keys %hash;
  }
});

##</code><code>##

Benchmark: timing 100 iterations of a, b...
         a: 274 wallclock secs (272.26 usr +  0.22 sys = 272.48 CPU)
         b: 366 wallclock secs (359.06 usr +  0.52 sys = 359.58 CPU)