I have written a script which compares multiple files and give the number of occurrence of each paragraph in each file. The script is working fine with smaller files but when applied to large files the program is stuck with no output. I need some help in modifying the script so that it can run on all files even if its very large. My script: 
#!/usr/bin/env perl
use strict;
use warnings;

my %seen;

$/ = "";
while (<>) {
    chomp;
    my ($key, $value) = split ('\t', $_);

    my @lines = split /\n/, $key;
    my $key1 = $lines[1];

    $seen{$key1} //= [ $key ];
    push (@{$seen{$key1}}, $value);
}

foreach my $key1 ( sort keys %seen ) {
my $tot = 0;
my $file_count = @ARGV;
for my $val ( @{$seen{$key1}} ) {
        $tot += ( split /:/, $val )[0];
    }   
    
if ( @{ $seen{$key1} } >= $file_count) {


        print join( "\t", @{$seen{$key1}});
        print "\tcount:". $tot."\n\n";
    }
}

[download]
please help me as soon as possible

In reply to modification of the script to consume less memory with higher speed by Anonymous Monk

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