my $mem1 = `perl -e 'print \`ps h -o sz \$\$\`'`;

##</code><code>##

my $mem2 = `perl -e '\$a = {A=>1, B=>2, C=>3}; print \`ps h -o sz \$\$\`'`;

##</code><code>##

my $mem1 = `perl -e 'print \`ps h -o sz \$\$\`'`;
my $mem2 = `perl -e '\$a = {A=>1, B=>2, C=>3}; print \`ps h -o sz \$\$\`'`;
print "$mem2 - $mem1 = ". ($mem2 - $mem1) . "\n";