如何使用Perl提供大型文件供下载？

#!/usr/bin/perl

use strict;
use warnings;
use CGI;
use CGI::Carp qw(fatalsToBrowser);
use File::Basename;
use File::Spec;

my $cgi = CGI->new;
my $filename = $cgi->param('file');
my $filepath = File::Spec->catfile('/path/to/files', $filename);

my $filesize = -s $filepath;
my $range_request = $cgi->header(-type => 'application/octet-stream', -Content_Length => $filesize);

if ($range_request) {
    my ($range) = $cgi->http('Range') =~ /bytes=(\d+)-/;
    open(my $fh, '<', $filepath) or die "Can't open $filepath: $!";
    binmode $fh;
    seek($fh, $range, 0);
    my $buffer;
    my $length = read($fh, $buffer, 1024);
    print $buffer;
    close($fh);
} else {
    open(my $fh, '<', $filepath) or die "Can't open $filepath: $!";
    binmode $fh;
    my $buffer;
    while (my $length = read($fh, $buffer, 1024)) {
        print $buffer;
    }
    close($fh);
}