#!/usr/bin/env perl

use warnings;
use strict;
use Time::HiRes qw( time );

my $file = shift @ARGV;
my ($fh, $time);

open $fh, "<", $file;
$time = time;
while(<$fh>) {
  /^ ?Query/;
}
printf "%f read lines from disk and do RE.\n", time - $time;

seek $fh, 0, 0;
my $s = "";
while(<$fh>) {
  $s .= $_;
}

open $fh, "<", \$s;
$time = time;
while(<$fh>) {
  /^ ?Query/;
}
printf "%f read lines from in-memory file and do RE.\n", time - $time;