C:\test>dir junk47.dat.*
26/10/2012  17:04        16,266,705 junk47.dat.1
26/10/2012  17:04        16,266,705 junk47.dat.10
26/10/2012  17:04        16,266,705 junk47.dat.100
26/10/2012  17:04        16,266,705 junk47.dat.11
26/10/2012  17:04        16,266,705 junk47.dat.12
...
26/10/2012  17:04        16,266,705 junk47.dat.95
26/10/2012  17:04        16,266,705 junk47.dat.96
26/10/2012  17:04        16,266,705 junk47.dat.97
26/10/2012  17:04        16,266,705 junk47.dat.98
26/10/2012  17:04        16,266,705 junk47.dat.99
             101 File(s)  1,642,937,205 bytes

C:\test>head junk47.dat.1
51 opt/src/1.tar 100444 1247464676 9476013183 283320 NA 1 0xbe2d 0x40000006
51 opt/src/2.tar 100444 1247464676 9802856445 283320 NA 1 0xbe2d 0x40000006
51 opt/src/3.tar 100444 1247464676 1116638183 283320 NA 1 0xbe2d 0x40000006
51 opt/src/4.tar 100444 1247464676 7417297363 283320 NA 1 0xbe2d 0x40000006
51 opt/src/5.tar 100444 1247464676 1416931152 283320 NA 1 0xbe2d 0x40000006
51 opt/src/6.tar 100444 1247464676 4827880859 283320 NA 1 0xbe2d 0x40000006
51 opt/src/7.tar 100444 1247464676 1016540527 283320 NA 1 0xbe2d 0x40000006
51 opt/src/8.tar 100444 1247464676 232543945 283320 NA 1 0xbe2d 0x40000006
51 opt/src/9.tar 100444 1247464676 3099975585 283320 NA 1 0xbe2d 0x40000006
51 opt/src/10.tar 100444 1247464676 6366271972 283320 NA 1 0xbe2d 0x40000006

C:\test>tail junk47.dat.1
51 opt/src/199991.tar 100444 1247464676 5569458007 283320 NA 1 0xbe2d 0x40000006
51 opt/src/199992.tar 100444 1247464676 6560974121 283320 NA 1 0xbe2d 0x40000006
51 opt/src/199993.tar 100444 1247464676 9388122558 283320 NA 1 0xbe2d 0x40000006
51 opt/src/199994.tar 100444 1247464676 5976562500 283320 NA 1 0xbe2d 0x40000006
51 opt/src/199995.tar 100444 1247464676 8576354980 283320 NA 1 0xbe2d 0x40000006
51 opt/src/199996.tar 100444 1247464676 5962219238 283320 NA 1 0xbe2d 0x40000006
51 opt/src/199997.tar 100444 1247464676 6407470703 283320 NA 1 0xbe2d 0x40000006
51 opt/src/199998.tar 100444 1247464676 7785034179 283320 NA 1 0xbe2d 0x40000006
51 opt/src/199999.tar 100444 1247464676 8945312500 283320 NA 1 0xbe2d 0x40000006
51 opt/src/200000.tar 100444 1247464676 4286804199 283320 NA 1 0xbe2d 0x40000006

C:\test>wc -l junk47.dat.1
 200000 junk47.dat.1

C:\test>type junk47.pl
#! perl -slw
use strict;
use Time::HiRes qw[ time ];
use List::Util qw[ sum min ];

sub process_flist {
    my ($name, $limit) = @_;
    my ($nlines, $total, @lines, @size);

    open(my $fh, '<', $name) or die("Error opening file `$name': $!\n");

    while (<$fh>) {
        my @f = split / /;

        next if @f > 10;

        push @lines, $f[4] . '/' . $f[1];
    }

    $nlines = scalar @lines;
    {
        no warnings 'numeric';

        $total = sum(@lines);
        $limit = min($limit, $nlines);
        @lines = (sort {$b <=> $a} @lines)[0 .. ($limit - 1)];
    }

    return ($nlines, $total, @lines);
}

our $L //= 1000;
our $N //= 7;

my $start = time;
my( $n, $t, @l ) = process_flist( 'junk47.dat', $L ) for map "junk47.dat.$_", 1.. $N;
printf "%.3f\n", time() - $start;

##</code><code>##

C:\test>junk47 -N=100 -L=20
147.615