Hi Monks, I have written a small script to process to files (which are of different file size each) the following way -

1. Open file 1 and create a hash of (key, value) pairs.
2. Open file 2, create a hash of (key, value) pairs.
3. Using the keys in Step.1, print the value from the hash created in Step.2.

To perform these three steps, I am using the following code (please excuse any inadvertent mistake, this is only my second Perl program).
 
#!/usr/bin/perl
   
use strict;
use warnings;
      
open(IHF, "<", "File1");

print "\n\n";
while( <IHF> ) {
           my %fets;
           my ($k, $v) = split;
           $fets{$k} = $v if defined ($k) and defined ($v);
           my @keys = sort keys %fets;
           my $trgt = getval(@keys);            
           print "$k     $fets{$k}  $trgt\n";
}
 
sub getval {
    my @k = @_;
    my %vals;
    open (JHF, "<", "File2");
    while(<JHF>) {
     my ($key, $val) = split;
     $vals{$key} = $val if defined $val and defined $key;
    }
    for my $i (@k) {
       return "$vals{$i}";
    }
}

[download]
When I execute this code on File1(of size 3.4 Gb) and File2 of size (1.4 Gb), the code runs extremely slow.
Can any Monks kindly suggest anyway to improve run time performance?
I appreciate it very much.

In reply to Perl Code Runs Extremely Slow by garbage777

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