I'm not an expert on garbage collection, but I played around with it awhile ago, and found out this tidbit..... you also need to undef the array, before it goes out of scope. This works.

#!/usr/bin/perl
use strict;
use warnings;

show_size();

{
    my @var=(0..1000000);
    show_size();

# undef before it goes out of scope
    undef @var;

}


show_size();


exit(0);

sub show_size {
    local $/;
    open(my $pfh, '<', "/proc/$$/status") || die $!;
    my $size = <$pfh> =~ /VmSize:\s+(\d+)/
               ? $1
               : 'unknown';
    close($pfh);
    print "Process size: $size\n";
}
[download]

Output:

Process size: 47936
Process size: 51976
Process size: 48064
[download]

As you can see, a bit of it is left over. Also it works in this simple example, but it may not in big complex scripts, or where objects are involved. </code>