Absolutely, unless there is some advantage to be gained by running computationally intensive tasks in parallel. Running I/O bound tasks in parallel almost never offers any time advantage (although sometimes there can be an advantage in terms or code structure).

However, it is very often the case that a smarter algorithm can provide a substantial performance improvement. For example, in the case of the code you show it maybe that you could use a hash to test or an IP match. Consider: 

use strict;
use warnings;

my @allIpsList = qw(10.1.1.10 10.1.1.17 10.1.1.125);
my %ipsMatch = map {$_ => 1} @allIpsList;

my $testFile = <<TESTDATA;
10.1.1.17
10.1.1.23
10.1.1.79
10.1.1.125
TESTDATA

open my $fh, '<', \$testFile;
my @found = check_fw_logs (\%ipsMatch, $fh);

print "@found\n";


sub check_fw_logs {
    my ($ipsMatch, $fh) = @_;
    my @matched;

    while (defined (my $line = <$fh>)) {
        next if $line !~ /(\d+\.\d+\.\d+\.\d+)/;
        push @matched, $1 if exists $ipsMatch->{$1};
    }

    return @matched;
}

[download]

Prints:

10.1.1.17 10.1.1.125

[download]

For real code you would probably want to normalise the IP numbers wherever they are used and of course you'd use external files etc rather then the tricks I've used to make this a self contained example.

True laziness is hard work

In reply to Re: Is Using Threads Slower Than Not Using Threads? by GrandFather
in thread Is Using Threads Slower Than Not Using Threads? by Dru

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