#!/usr/bin/perl
use strict;
use warnings;
use Tie::Hash::Sorted;

my $sort_by_value = sub {
    my $hash = shift;
    [ sort {$hash->{$b} cmp $hash->{$a}} keys %$hash ];
}
tie my %sorted_hash, 'Tie::Hash::Sorted', 'Sort_Routine' => $sort_by_value;
%sorted_hash = (k1=> 'v2', k2=> 'v1');
print "$_ : $sorted_hash{$_}\n" for keys %sorted_hash;