This all depends on how much you are exactly storing in your hash tables, but this code should give you a hint, just run it and watch top or some other resource monitor: 
#!perl -w
use strict;
$|=1;
my (%a,%b,%c);
for (0 .. 500_000) { # set higher if you dare
    $a{$_} = "x" x 60; # 60 character string
    $b{$_} = "x" x 60;
    $c{$_} = "x" x 60;
    print "\rrow $_" unless $_ % 10000;
}

[download]

note: this goes up to 190 mb for about 500_000 iterations on my machine YMMV.

"What should it profit a man, if he should win a flame war, yet lose his cool?"

In reply to Re: Space Efficiency of Hashes by Joost
in thread Space Efficiency of Hashes by Anonymous Monk

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