In general: Your problem might not be the keys, but the values of your hash. 
#!/usr/bin/perl

use warnings;
use strict;

use Devel::Size qw(size);

my %hash = ();

for my $key (1..27000) {
    $hash{"blahblahblahblah$key"} = 1;
}

print size(\%hash);

[download]
The keys are really not small here and they also contain a hell of redundant data. But size for the hash speaks of 1736142 bytes. It also has 27.000 entries like yours. I think your optimizing on the wrong part of your data structure.

Bye
 PetaMem     All Perl:   MT, NLP, NLU

In reply to Re: memory consumption skyhigh... by PetaMem
in thread memory consumption skyhigh... by spx2

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