Can you characterize the processing that you're doing on lines from this file? If it's compute intensive processing (with no program induced blocking for I/O), then you're not liable to see much improvement from processing sections of the file in parallel.

Where multiple processes or threads win is where the processing involves activities that block for IO.

Currently my code is doing ...

foreach $keyword ( @ARGV ) {
        $key= join(' ', split(/\+/, $keyword));
        $remote = IO::Socket::INET->new( Proto     => "tcp",
                                         PeerAddr  => $host,
                                         PeerPort  => $port,
                                       );
        unless ($remote) { die "cannot connect to http daemon on $host
+ on $port" }
        $remote->autoflush(1);
        print $remote "GET $prefix$keyword HTTP/1.0" . $BLANK;
        $count="0";
        while ( <$remote> ) { 
                if (/flist/i) {
                        $count++;
                }
        }
        print "$key,$count\n";
        close $remote;
}
[download]

And I am redirecting the output using >
It's a pretty basic bit of code it just gets complicated when it has to automatically run itself 8 times over different parts of the arrary. (I say 8 times because after 8 a performance degradation takes place, 8 seems optimal and can finish doing the process in 40 minutes.)

Cheers,

Mark