Run this simple program with minimal processing against your data and post the results. This will help eliminate one potential source of your problem (i/o) and provide a better indication of your data than just a size of 50M

#!/usr/bin/perl
use strict;
my $t0 = time;

my $file1 = $ARGV[0] || 'ficc.txt';
my $file2 = $ARGV[1] || 'fic.txt';

my $count1=0; my $words1=0;
open FICC,'<',$file1 or die "$file1 : $!";
while (<FICC>) {
  my @words = split /\s+/,lc $_;
  $words1 += @words;
  ++$count1;
}
close FICC;

my $count2=0; my $words2=0;
open FIC,'<',$file2 or die "$file2 : $!";
while (<FIC>) {
  my @words = split /\s+/,lc $_;
  $words2 += @words;
  ++$count2;
}
close FICC;

my $dur = int time-$t0;
print "
File1 : $count1 lines $words1 words in $file1
File2 : $count2 lines $words2 words in $file2
Time  : $dur seconds\n";

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poj

In reply to Re^5: compare two text file line by line, how to optimise by poj
in thread compare two text file line by line, how to optimise by thespirit

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